I'll have to have you stop over to watch a movie or a game.
I have Joe and they look the same. I also have watched HD movies on my TV and its the same. 720P is HD just not "full HD" but it doesn't matter unless it's over 50". I've heard that from more than 1 person as well.
Some differences that may matter I think may be.
Viewing angles Plasma any angle LCD straight on or slight angle. +1 for Plasma
LCD performs good in any light Plasma is best used in rooms without a lot of windows(glare from the glass screen) or at night. +1 for LCD.
Which is funny because my TV is in a room with 4 sky-lights and 3 big bay windows, but I watch TV at night 85% of the time and when I don't there is heavy curtains.