I posted this in another thread:
I had a 42inch Westy LCD 1080P TV now I UPGRADED to a 768P 50inch Samsung Plasma. I personally feel that you will not be able to tell any difference between 1080P and 1080I/720P on anything 50inch and lower (might be a difference if your display is 60inch or bigger). My brother has a 1080P 56inch Samsung DLP and his Blu rays through the Ps3 looks just as good as my blu rays and 768P Plasma through my ps3. In some respects, I feel my plasma is better because it does not loose its viewing angle as easy and seems to have more of a picture tube type look/feel to it (more of a pop). I think you will see a huge difference even at 1080I or 720P when watching blu rays or hd dvds.
I sat 8'ft away from my 42in LCD and now Sit 8ft away from my 768P Plasma. I still feel the Samsung Plasma is superior in overal picture than the Westy but the resolutions seems to be the same. My brother seating postion in his living room is about 10.5 from his 56inch 1080P DLP.
PS...I have 20/15 vision (better than 20/20) LOL....but I am serious.
I run a pioneer 6070 and the pioneer 94HD bluray player, i haven't rented a DVD since i got the bluray player. I'm even going back and watching old movies (something I almost never do). It's really a significant increase in picture quality and sound quality (when using TrueHD or uncompressed PCM).