You can view HD-DVD movies when the HD-DVD player comes out for the Xbox 360.
If you're stuck between which one you like, just do some research. See which console has the games you like. Personally I want an Xbox 360 because I feel it has better games like Gears of War, Halo 3, Forza Motorsport 2 etc. The PS3 is a pretty powerful console though it is a bit expensive and hyped up if you ask me, but it has some great games like Resistance: Fall of Man or Gran Turismo HD.