There are a lot of images if you Google "TV wall decoration". 20' is a lot. I'd have trouble with it too because I don't like clutter around my TV (too distracting). Our TV wall is 14' long (10' ceiling). We have a 7-1/2'media cabinet below the TV, and to the left of the TV, a very large "poster". On the media cabinet, to the left is the cable box and a plant and to the right is a lamp. That's it.

There are lots of threads here and other places about how to create a built-in look with ready made pieces. How big will the tv be and where on the wall will it be placed (i.e. center, left third, right third, etc.)? Here is one pic using Ikea pieces. If you google "Ikea TV built in look" and similar, you'll see lots of ideas.

I have a similar problem on a smaller scale. Layout sounds very familiar. We didn't do built-ins because my DH did not want all the clutter so now we have a new beautiful low and long antique console on the wall but it only takes up half the space horizontally and not much vertically. I feel like this expanse of wall is bedeviling me. I am considering sconces as in this inspiration photo. At the moment I regret not having the built-ins because I need places to put my "stuff". Perhaps that was what DH was trying to avoid. I'm curious to see other suggestions and ideas. I think the Ikea idea is great and might be a cost-effective solution for you with such a long wall.

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I have something similar, and I hung a large tapestry on the wall behind the tv. love it.

Here's a link to that thread with a pic. I tried "linking" it but no go:

http://ths.gardenweb.com/discussions/2817653/so-relieved-no-more-big-blank-wall?n=31

That's a great idea violet! Here is another photo I found that could be a lower cost option for a large expanse of tv wall.

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