A pair of large leaning floor mirrors to reflect back the light from the windows will make the room brighter and feel larger and will break up that large expanse of wood.

In terms of the style, you don't need to get too precious with the period vibe. It doesn't need to look like it marched straight off the set of "Mad Men" to work with your other mid century pieces.

We just moved into a home with real wood paneling in the living room. My first thought was to paint it all white, thinking it would look like a beautiful bead boarded cottage and give the room some light, but the owners of the house want to keep it in it's original 1920's state, stained a similar color to yours.

Instead we have hung art, gallery style on the large expanse of the one wall with no windows. It has significantly opened up the room, by adding color and reflecting light from the glass and mirrors mixed in.

Definitely art of some kind. 4 big matching pieces hung at the same height and spaced evenly (mimic the big windows opposite).

4 old movie posters, or concert, or a series from an Etsy artist... or you could even pick up 4 sheets of handmade paper from a shop like Flax.

Rub the paneling down with Howards Wax and Feed, it will hightlight the luster.

I also thought some really large pieces of artwork or framed posters (or a whole bunch of smaller pieces) would break up that huge expanse of wood and give you some brighter or lighter colors. Weren't there some posts recently about framing fabric or wallpaper to make "art"; something like that might be really nice if you don't already have a lot of art that you like.

we have a mid century home too (no wood paneling though) I'm not a purist, but I think it'd be ok to paint one of the wood panel walls. A wood credenza would pop a lot more with a neutral background.

It's beautiful, all it needs is a wonderful, artistic, huge framed photograph.

I would paint the wall - I live in a mid-century modern and from my guess it is just veneered wood paneling (ie.not precious). If you like the wood that is one thing, but it darkens and overpowers the space.

Definitely hang things on that wall.

My initial thought wasn't large pieces of art or a series of framed posters, but rather a family photo wall.

If that is too casual a vibe though, then turn to posters. Good art is a serious commitment, and involves a lot of effort and education. It's a hobby and passion in and of itself. If it is not yours, isn't of hanging mediocrities (like on the home show I saw last week, where the expert just went to a canvas with paint brushes and wall paint and called it "art"), then turn to something that is. Perhaps assemble a collection of vintage movie posters -- for example, different posters from different countries for the same movie, or a collection of posters with some other theme -- all one actor (Alain Delon, for example, or Liz Taylor), or all one director, etc. Have fun with it.

A few ideas:
A mirror grouping (hexagonal mirrors maybe?) - A brightly colored tapestry like the ones they have at Urban Outfitters - Some shelves with framed photos or collectible displays...

Paint/stain wooden plywood some bright color and attach with spacers on the wall, so they are floating panels

I wouldn't paint it or employ mirrors - use art . Original oils on canvas would add even more texture, and vintage pieces may be more affordable and fun. As for a wood credenza - we have one on our mahogany-clad room divider that seems to work, although the wall doesn't go all the way to the ceiling:
http://www.flickr.com/photos/25671211@N02/6565158409/in/set-72157626602351222/

colorful art

I was just married & moving into my (now) husband's home was also faced with a whole huge living room of "authentic" wood paneling. I wasn't quite sure what to do with it either, but we painted it... and wow oh wow, I'm glad we did! I thought it would look "cheap" to just paint over it (we did a sort of creamy, light light beige) but it looks great. You don't even notice it's paneling without looking closely. So, in my book, paint is the winner!

agree with bluestu77, if you have to turn the light on to take your photos then go lighter.

I like the idea of a couple of credenzas, white and a little curvey, along the wall. I have seen this style around but, personally, I would end up painting a couple of vintage ones myself. You can then prop large mirrors on top of them to create the symmetry that has been suggested a number of times. I'm willing to bet you wouldn't want to mark up your walls too much. One credenza will be too small against such a long wall and, if you place one in your "dining area" and one in your seating area it will help define the space and give you a place to set dishes during big gatherings. It will be tricky to get the right size of credenza, no question. Too small and they will look silly, too wide and they will block traffic. Good luck! I don't think you will have to paint the walls (especially since you like them) but I do agree that you shouldn't feel too tied to the period unless you want to have fun with it! If you respect the shapes and colours that you already have (and I'm certain you will) you'll make good choices regardless of the period the product was made in.

You don't need to necessarily paint the paneling (I love that you want to keep it period appropriate!) but I think if you want to keep the wood you should definitely add more lighting to the room. A lot of why it looks so dark right now appears to just be insufficient light, not the wood. I also think large scale art in brighter or lighter colors would look great. I wouldn't go with a gallery wall, I would go with a neat row of frames the same size, because it would look good with the row of windows the same size you have on the other side of the room. Also, maybe you could find a credenza on craiglist or somewhere that isn't in perfect shape so you don't have to feel bad about painting it? And then just paint it a color that will go with whatever art or textiles you've brought into the room already.

Years ago I bought a house with similar wood in the living room; it was so dark. I finally painted it and never regretted it. It opened up and brightened the room, really lovely. That would be my suggestion.
Carol

Textile art! Something light-colored and shaggy. Maybe even a large rug that you really love.

It looks like there is chair rail towards the top of the wall (probably not the right word since its not chair height). Paint white either above or below that line to lighten up and modernize the space without loosing the mid century feel.

I LOVE the paneling and think some artwork would be a great way to break up the wall. Also, and this might be crazy, but a fun color on the ceiling might add some pop to the room. Maybe a yellow or teal.

I would paint it. Decorator white. And if it still seemed kind of dark I'd hang a mirror and one large, colourful artwork. But I like a lot of bright white, maybe that isn't your thing.

Even if you paint it, you still will need some art, so I would start with the art (even framed wallpaper) and see what it looked like before painting.

I have an all wood house, and at first it was tempting to paint because it was just so different from what I was used to. After living with it for a few months and seeing all the natural light, I am very glad I did not paint. I came up with other ways to brighten the space in areas where it was needed. But honestly, there is a lot more light than people can see in a snapshot photo. Mirrors can work but they do reflect what is around them -- your room needs some art.

Is it possible to:
1. only keep the panelling on one wall so it's not overwhelming, and
2. change out fixtures on that one wall to streamline the look (vents, light switches etc.),
3. add shelvings and very simple modern frames of similar materials as the panelling to break it up
This is not an ad, but I stayed at Hotel Le Germaine recently. Their rooms were covered in wood veneer panels but the design is so modern (think minimalism + modern mcm), it was very inspiring.

This place has such fun potential. I think if you want to embrace the wood walls you can do a lot just by breaking up the wall visually/texturally, and I think adding lamps will warm the place up.

I think a low credenza with a MCM lamp (but modern shade) will warm up the space lighting wise, then maybe above that hang colorful artwork, or to make it really period I think a brass MCM wall art hanging. To even further add texture/color you could stack a few colorful books on the credenza, or even buy a brass bar tray and have a carafe or drink set out for display. As far as the credenza material I think you should probably just go with a lighter shade of wood. Mixing woods is ok if you have some contrast. You clearly caught me on my lunch break, I'm too excited about this one...

Some things:

http://www.etsy.com/listing/78876841/stunning-vintage-metal-wall-sculpture?ref=sr_gallery_7&sref=&ga_search_submit=&ga_search_query=mid+century+modern+brass&ga_view_type=gallery&ga_ship_to=US&ga_page=3&ga_search_type=vintage&ga_facet=vintage

http://www.etsy.com/listing/86113113/mid-century-modern-lamp?ref=sr_gallery_12&sref=&ga_search_submit=&ga_search_query=mid+century+modern+brass&ga_view_type=gallery&ga_ship_to=US&ga_page=3&ga_search_type=vintage&ga_facet=vintage

http://www.etsy.com/listing/87253675/mid-century-brass-and-wood-lamp-nice?ref=sr_gallery_13&sref=&ga_search_submit=&ga_search_query=mid+century+modern+brass&ga_view_type=gallery&ga_ship_to=US&ga_page=2&ga_search_type=vintage&ga_facet=vintage

younghouselove's blog had wood panelling through much of their house and they painted it a nice bright green, which i know is not everyone's cup of tea but hey it really brightened the place up a ton. their house is also a mcm ranch so i think you'd get a lot of inspiration for their place. and i definitely think that's what you need here, just a little inspiration. and some art.

http://www.younghouselove.com

A while back Apartment Therapy had a house tour (link below) which featured some lovely wood paneling on a couple of walls in the home. Maybe this will give you some ideas:

http://www.apartmenttherapy.com/marks-original-mid-century-mod-162638

My first thought was an oversized art, too. Maybe even a fifties-style decal. Wood panel can be cool! Don't paint it, this won't look cute&cottagey, your place if more mod. Check some Palm Springs hotels for style inspiration :)

I was thinking of the wall decals in mass could be cool. What about something like this:

http://www.interlam-design.com/Elements_ProductList.cfm

that you create yourself with contact paper? Cheap and super cool. If it was white paper, it would lighten the space up, look amazing with the wood, and the whole wall becomes its own art piece.

No paint, no strange mirrors. Just art. Black and white photographs framed well would look so striking. Good luck.

Do nothing, in time it will become ultra cool again and everyone will think you are cooler than the cool. Mr/Mrs Sub Zero