how big is the area your TV is going to be in? I know there's some sort of ratio as to how big the TV is in relation to how far away you sit from it. And 50 inches for LCD is kinda pushing it.
Edit:
I found that rule.
"A rough rule of thumb is to sit between 1.5 and three times the screen width distance away if you're planning on buying a widescreen television. For 4:3 screens, it's at least up to three times the screen width away. So if you're looking at a 42" widescreen, for example, your couch needs to be at least 1.6m away. For 60" widescreens, that increases the distance to roughly 2.3m away."
Taken from:
http://www.cnet.com.au/tvs/0,2390352...53522,00.htm#1