I think a colorful rug, pillows and some art on the walls would be a good start.

I'm a plant lover, so I would have that window lined up with various plants in mismatched pots in no time!

Colorful Art is Definitely a good place to start. I would try breaking up some of the black. Maybe a table runner (if that is not too weird) on top of the TV stand to break up the large black area and some coordinating pillows or blanket/throw on the couch. If you are on a budget you could dye the curtains something bold (I'm thinking a bright red to go with the navy that could be pretty regal but I hear Salmon is a nice coordinator with navy these days too. Could also try a monochromatic color scheme like a deep purple or a teal green to go with the blue. Either way if you bring some color in and some art on the walls I bet you feel a lot more at home.

bright color photographs and pillows, new drapes. do something with the flower pot, make something that you would want to look at.
maybe hand a nice wall carpet.

drapes, more plants, a nice rug. i would also personally get some colorful throw pillows or a blanket or something to help lighten up the couch.

Big fab loud curtains! Pick a fun pattern and run with it! A bright throw on the back of one sofa? Could you switch out that dark table for a glass one, or paint it a fun, zesty color? How about hanging a mobile in the corner? As for colors, how about silver or bright green?

And yes - more plants!

also. you could mount the tv to the wall (if you are allowed) and frame it for a more 'put together' look, and maybe find a cheap buffet/dresser on craigslist and fix it up/paint it, take the drawers out, and stick the speakers in there, to make it easier on the eyes.

references to what i'm talking about:
framing the TV - http://media-cache-ec3.pinterest.com/upload/52776626852769509_TflpGyc4_c.jpg, http://media-cache-ec6.pinterest.com/upload/17451517275537430_KEC1wDiS_c.jpg

dresser into a media center - http://media-cache-ec5.pinterest.com/upload/88735055128130937_bqGohmCI_f.jpg

Regarding inexpensive art: Buy outdated calendars with pictures you love. Find inexpensive frames and they you go.

Art definitely! There's a lot of stuff in your apartment but those bare walls could hold tons of color. There's been some good DIY here lately on making your own patterned wall art.

Black(I assume those sofas are black), navy and white can look very crisp, tidy and a little preppy. White pillows with a black graphic in the sofas, mixed with white with navy border (or similar) pillows, a woven throw in white and two blues, black picture frames with white matting, a crisp white roller shade for the window if you can afford it, a white ceramic tray to hold items on your coffee table, maybe a corner shelf unit in white...would all lighten the mood. The speakers are one of those things that come with boyfriends. Maybe you could fashion or purchase lightweight, open-sided boxes to partially contain them, and cover that with pretty (draped-over) textiles when not in use? Sort of like those MDF table rounds decorator stores sell to be draped with table cloths and used as side tables.

Dump yer man! LOL :)

...kidding, but I once lived with a DJ for 4 years. It was pure madness with all the records and unsightly speaker/ tech stuff. My advice would be to try to organize and disguise as much as possible. Ikea has some great items you can "hack" to store things nice and neat. I recall the Expedit being a god solution to 12"record storage. Plus you can add some decor to the empty cubes.

http://www.ikea.com/us/en/images/products/expedit-shelving-unit__0092718_PE229441_S4.JPG

Here are some other ideas:

http://www.ikeahackers.net/2009/02/hack-dj-console.html
http://www.ikeahackers.net/2009/02/spin-it-with-some-colour.html

Put a floating click together wooden or laminate floor over the carpet. I saw some recently at home depot for less than a dollar a square foot. When you move, take it with you. Then, layer an area rug or colorful Flor tiles on top.
Make friends with spray adhesive and fabric. You can't paint but you can stick fabric on your walls, plain or printed. When you move, pull it off and take it with you. It won't leave any traces.
Find some radiator cover metal stuff with the fancy perforations. Find a small cheap side table. Put the table over the stereo speakers. Put the radiator cover over the legs of the table. You should be able to find something inexpensive at ikea. When you leave the boyfriend, take the tables.
Replace some of those leather monstrosities with upholstered chairs or something more open.
Accentuate the height of the window. Hang canvas drapery panels right up to the ceiling.

Follow everything Rural and Rueful suggested. I Would also suggest getting several low cubes or crates line them up next to each other and place a piece of wood over them so it looks like a low built in storage bench that wraps around from window that lonely plat you have in the corner. Then place the tv and speakers on/in it. good luck

yes to art, curtains, throw pillows, plan ts and a rug. also, paint whatever furniture the tv is sitting on. get some shelves or at least wood crates that those speakers/tv & audio equipment will fit in and paint them too. camouflage one of those sofas with blankets or quilts or colorful throws so they won't look so matchy-matchy and cold - drape one over the back and wrap another around the seat cushions. paint the coffee table - all that furniture is too dark. get the junk out of there (is that luggage in a corner? get rid of it)

I recommend floor to ceiling curtains with a great pattern to really focus on that big window. And an area rug to break up the darkness of all the furniture and carpeting. As everyone else said here, accessorize with pillows and art.

Definitely a colorful rug.That will help a lot. Also, gallery-style for your printed art and pictures would be fun, and definitely include some mirrors to enlarge the space.

I would put temporary wallpaper or DIY removable fabric wallpaper under the chair rail!

What a great space! I don't know your tastes but I might put a chunky shelf in that corner to display books and statues, maybe remove all but a few glass bottles from the window sill. That window is great. Also a colorful throw blanket, and chunky tables and foot rests to make it more cozy and neat. Best wishes, I know new spaces can be challenging.

Also my 2 cents, don't waste your money on cheap pieces. Invest in pieces you love and can keep for life. Personal experience.

I would pick a definite accent color.. you have white, navy and black... how about a butterscotch/gold-yellow? or a nice orange? or lighter blue? get large, patterned floor-to-ceiling curtains with the color you pick.. pillows in the same color... bind up any loose cords from that entertainment center, and maybe mount the tv on the wall if you can.

So what actually happens if they say "no paint" and you paint anyway? (you'd just have to paint it back before you move...) you could PROBABLY get away with breaking up the wall by painting the bottom half with "almost white" pale gray.

it looks dark in there. LAMPS!

large framed posters would look good in there.

and i agree with the person who said plants in the window sill.

and what the heck is that giant black thing in the corner next to the couch? can it go in a closet?!

oh and on second thought, it looks like that room is a little awkwardly situated for the furniture you have. Do you plan on having lots of people over often or could you handle losing either the loveseat or the couch? they look crowded and it looks like the walkway through the room goes right between the tv and the couch.

move the couch up so the walkway goes behind it (hopefully that leaves enough room so you're not like 2 feet from the tv?) and put the loveseat in storage (or mail it to me! lol)

you can get a cool sideboard table or china hutch-style thing to put where the couch is now for books/movies/etc?

I'd definitely lighten up the couches with white throws and get rid of the coffee table or replace it with a glass one. Colorful red and yellow artwork and a colorful rug and pillows. Also, that plant looks so lonely in that corner. Maybe get it some friends. :)

Lighting!
No one has mentioned lighting. The pictures posted only show window light and some sort of out-of-frame overhead light. Get yourself some lamps. A couple of floor ones, maybe a small table ons for the tv stand area, a reading light for the chair by the window. You can add all the color in the world to this room with accessories and surface decor, but no one will see it without proper lighting. Plus, you can always take them with you!

suggestions, try layering with lively elements, stop when it fells like enough

would be friendlier for conversation if the seating faced each other

with a lighter coffee table in between, maybe paint with a "pop" of mustard or eggy yellow?

tall plants in front of that tall window, dramatic needle cactus or norfolk pine or fiddle leaf ? or rubber tree plant depending on the exposure

curtains in a vivid pattern

cozy bright throws on the seating

big art on the walls, paintings, wood blankets, photos, seascape, portraits, whatever you love

Cathryn and some others here have hit the nail on the head. Lighting will do WONDERS for the space. Paint, area rugs, and pillows are expectedly great improvements, as are robust indoor plants. A main point I noticed is how low everything is in your photos - furniture, plant, TV, etc. Low can absolutely be minimalist and beautiful but that line that runs across the room just cuts the space in your home seem smaller than it is. Place that TV higher, bring in taller, mature indoor plants that will break up that line. Utilize the high ceilings you love to hang higher window treatments (artwork should generally be eye level). The sky's the limit!

A flat-weave graphic rug makes an awesome throw for a sofa. Avoid rugs that are too prickly (although I'm using one and I love it, pricks and all). This room cries out for some light. Placing the tv on a Parsons table (West Elm) in a light wood, white enamel, or metal would help to make it look less like a black hole and change the hieght a bit. it looks like the speakers are too close together for good definition, but I can't tell from the photos if there's anyplace else to put them. Rather than many pictures of different sizes, you might think of getting some photos blown up on canvas. There are any number of services that do this; the print wraps around, so no need for framing, which is expensive.

I agree that the seating seems awkward: facing is definitely better if it's possible. If they must be in an L shape, perhaps putting them quite close to each other with a small side table or a basket at one side might work. The coffee table is too small and the rectangular shape seems repetitive. Look for a round or square table to make the space less rigid. I like the Origami table from West Elm.

The curtains should be longer. Curtains are ridiculously easy to make. Ikea has any number of curtains which could be used as well. Or king sheets. The items on the window sill should be grouped more tightly. Or perhaps just put a big healthy plant on the ledge.

The plants look like they need attention: get some larger, healthier ones and don't stick them in a corner like an umbrella stand. Also the

With the black sofa and dark carpet, you have created a black hole. Lighting up the floor space with a light cream rug. Also, balance your room and draw your eye up with thrift store picture frames painted a nice subtle color. A mirror would help out too! http://www.google.com/imgres?hl=en&sa=X&biw=1920&bih=965&tbm=isch&prmd=imvns&tbnid=RydoVLE8stQtmM:&imgrefurl=http://yourdecoratinghotline.com/style-trends-2011/&docid=oJC10VXx4IuhOM&imgurl=http://yourdecoratinghotline.com/wp-content/uploads/2011/03/access-frame-art-nestingPlace.jpg&w=298&h=450&ei=-s9hUPaDOuvPigKj_oBo&zoom=1&iact=rc&dur=675&sig=112413381957045922872&page=2&tbnh=145&tbnw=96&start=51&ndsp=60&ved=1t:429,r:22,s:51,i:307&tx=44&ty=53

Before you go mad on soft furnishings. It may be an idea to stop smoking indoors.

When I first moved into my own place I smoked my head off, it was great. Only when I went to repaint a year later did I notice how disgusting the ceilings etc. were. And how almost all my fabrics reeked of smoke. Haven't smoke inside in the two years since.

Just an FYI... Best of luck with the new place!

A big mirror might be nice on the wall that's 90 degrees to the big window. An artsy homemade simple mobile (thin wire w/ paper parts or plexiglass) would draw your eye up and celebrate the play of light between the two surfaces.