Think outside the box. Many TV cabinets I see in the stores and on the Internet have an open compartment for the equipment to be housed. Personally, I don't design a room and want all these things showing; the DVD player, cable box, router, sling catcher, etc - it's just ugly. It's hard enough to hide all the cords.
I find body styles that can be interpreted and become a TV cabinet. 60"W x 30"H x 20" is good size depending on the size of your TV itself. Of course, save room for speakers too. The use of Frosted Glass or a wood grill will allow the Infa Red to work with your remote controls. The cabinet also has to be designed to store all those DVD's we accumulate (and music CDs).
Viewing distance recommendations are approximately 6 to ten feet for screens sizeed 37". A 42" plasma display may be optimally viewed from 10-14 feet. A 50" plasma display will look best from 12-16 feet, and you should have at least 15 feet to work with when installing a 60" or higher.
I used the body style below and added a decorative top in the raw wood look. It matches the dining table. Then painted a shabby distressed cream.
Many of my customers comment they don't want to see the TV in the living room - they don't want it the center of attention. Well, let's face it - our flats are small for most of us and we no longer have family rooms. The gathering place is the living room and many of us gather around the TV. Don't try to arrange the room to hide it - arrange the room to cozy it up.
This is my TV cabinet - I decorate in a French country feel. This was an antique Chinese Cabinet that I had painted and changed out the doors.
This is one I designed. I saw a sideboard that was sold and copied the artwork. Then added the abstract panels for the TV equipment. It's only painted orange on the front. The rest is a dark brown stain on the top and sides.