We have a 50 inch TV and I think it is more than big enough, but I know that there are TV's even bigger than that. Should you really get a bigger TV in a small space? Or does size matter at all? Does the size effect the quality of the picture?
It really depends on your preference. An LED is probably the clearest one out there nowadays. You will have a great picture at 25 inches and a great one at 80 inches. It's just preference of how big you want the television to be. For example, if you're setting up a kitchen TV, go for a small one. If you're making a home theater, 50+ may be applicable.
I think a really big TV only affects the picture quality if you are sitting too close to it! Something proportionate to the size of the room is ideal. But bigger is okay as long as it's not like being at the front row of the movie theater!