open upper shelving or a mirror

I am assuming that is a fireplace in the corner and a window on the left? You could always mount it on the back of the closet, using a swivel mount

How big is your couch and how big is the living room? The only thing that comes to me is to put the tv on the wall against the bedroom and the couch in the center of the room facing it, but that would only work if room allows. Otherwise you could do couch against wall and tv centered, but you might need to think about specific furniture for the tv. Depending on how much tv you watch you might consider a cart of some sort to keep the tv tucked away until you want to watch it.

It's hard to tell what the scale of the rooms are without dimensions so this might not work if the space is too small... but here's an idea:
Place couch facing window so you view the back from the entry/dining area. You could place a narrow console behind to place keys, phone etc when you come in the door.
The nook could have another small console or chest of drawers staked with a few well chosen objects/books (with a lamp on top to highlight the nook as a feature). the TV then goes on a mounting bracket on the empty wall to the left of the window surrounded by other frames / pictures to disguise it a little.

But this might look cluttered if there's not a lot of space to start with!

I would use that long wall for the TV/bookshelves and float the rest of the furniture in the room. The nook I would use for artwork.
If you are going to be using the door that says "entry" to enter your house (rather than coming in through the garage), you will need something near the door for keys, bags, etc, and having shelving on the wall would help with that.
Enjoy your first apartment!

Not sure if this will work because we don't have the dimensions, but assuming it will fit: Could you create an entry way area by placing a low shelf or sofa table on an angle following the line that divides your dining and living room, and then put your sofa in front of the table, so that the sofa faces the (fireplace? entertainment centre?) that is also on that little angle, and hang your TV over the fireplace? Then position armchairs to make a diamond shape in the room? If not, or if you want to keep the space between rooms open, then I think your TV needs to go on the wall on the back of the closet near the kitchen, with your sofa on the opposite wall. But to me, a console table along that entry way makes sense! That nook would be great (as others have suggested) for a few built in shelves or a bookcase, or some art.

At the risk of committing AT sacrilege, you could mount a flat screen TV above the fireplace, then angle your sofa parallel to the fireplace and the apparently tiled entry flooring. Put a console behind and a couple of chairs perpendicular to the sofa. In that niche, a lot depends on what it looks like in person, and what your fireplace looks like -- whether there is a wide surround or whatever. A small table or cabinet might fit, triangular shelves could fit into the corner, a large framed piece of art, a potted ficus tree, any of a number of options might make that corner look good...

If over-the-fireplace doesn't work for you for the TV, I think I'd consider putting it on the window end of the bedroom wall and trying to fit your seating so you can mainly watch TV and have some seating facing the fireplace, if only a reading nook. (Maybe a pair of swivel chairs that can go in either direction and a sofa facing the window.)

It's a tricky space. Good luck with it.

Again depending on the size of the room - would it work to put the couch on a diagonal with its back to that open entry way (assuming again you have enough room for all traffic. A console table behind it as well to anchor the placement. With this you are embracing the fireplace, the tv (if you mount the tv either over the fireplace or to the right of that nook) and the window I believe is on the left.

Depending on the size of your couch you could float it at the same angle as the fire place and use smaller pieces around the rest of the room. Put the TV above the fireplace and that area will become the focal point. Use the nook for either storage, an art display or for a mirror. To make this look more intentional you could also use a rug going in the same direction. Good luck!

When I had a corner fireplace, the only thing that looked right was to angle the sofa so that the fireplace was the focal point. If possible, I would hang the TV over the fireplace and place the sofa parallel to it.

I think you should float the furniture and maybe ignore the fireplace. Corner fireplaces always look like someone wedged them into a corner. It might look nice in your periphery but don't make it a focal point. This will help you with the layout.

For those trying to figure out the scale of this space, a good tip is to make an assumption that the entry door is 3' wide - use this as a scale.

I would suggest something similar to what HollyR proposed...
Put the sofa facing the window with a console behind it and use the nook for artwork (or possibly floor lighting...it may feel too unanchored there). Perhaps you could put the TV on a piece of furniture under the window. The long bedroom wall could have two small scale chairs and a table with lamp.
The TV may not be centered on the sofa, but I think the window and fireplace side of the room will feel balanced, as well as the room overall.

It's too bad you can't add an actual photo of your place. It would help to give suggestion. So far I'm agreeing with MOMMY1043 - angle the couch parrallel to the fireplace. I would add a sofa or console table behind the couch and place lamps or other decorative items. The console table would also be a good place for a catchall for keys and stuff when you walk in. Good luck in what you decide to do!

One question for A.T. and or you...

You take the time to upload a floor plan, but you don't have a digital/camera phone for a pic?

Diagonal.

Does your TV have to be the focus of the living room? You could always mount it on the closet wall with one of those mounts that you can pull out ant turn towards the couch.

I have several suggestions:

1) Watch tv in your bedrooms and leave the living room mess free.

2) Make the tiled dining area a small tv/den area. Just throw down an area rug and put in a couch or a few chairs and make the living room a formal dining area or formal living area. Making that livingroom a formal dining area would be fabulous during the holidays.

3) If the wether is nice in your area, you can even put the tv on the porch. If you turned the tiled dining area into a living area that could be extended to the porch by the addition of french doors, the doors could be opened to accomodate more seating and guests.

A spare bedroom can be used as a tv room. It's great because it has a bathroom and you can turn the closet into a butler's pantry equipt with a mini fridge and microwave!

Close in the garage, add a fireplace and a pass-thru bar to the kitchen. taa daa!

Diagonal is a good idea! If you never use the fireplace, you can clean it, close it up, and put a tv inside it, face the sofa toward it and put a sofa table along the back of the sofa. Or use the mantle as a tv stand.

It's hard to tell. But here's how I will decide.

1. I would place the TV where the power sockets are, to prevent tripping and hide the wires. And have the bigger sofa facing it. But without dimensions, it's really hard to tell. Get a 2+1+1 seating format so you can move around the furniture as you see fit.

2. If you like the fireplace and will use it, make it the focal point. Have two armchairs on either side of it. And a 2 or 3-seater placed opposite, its back facing the dining. Your tv can be placed at the opposite wall.

3. If you have already decided where to put the furniture but do not know what to do with the nook, you can hang a painting, place a full-length mirror leaning against the wall or put a beautiful sculpture or plant. If you need extra storage, put a shallow side cabinet and place some pictures on them since it's near the fireplace.

I don't care where you put the couch or tv, really, it depends on their size and how they look in the room. But that nook, as you call it, is just a wall, not very wide, and if you put anything very deep there, it will physically and visually get in the way of the fireplace. So think accent piece only there, very shallow, like a small not deep at all bookcase or console, with art above it maybe, or a tall bookcase if you can find one not deep. Oh, and your TV does not in any event have to be centered to the couch. And you don't necessarily need to have a couch, depending on the room it may be better with chairs only.