PS3 will definately be neat. $600-$700 for a game system is a big much for me for the base unit.
It all depends on how hardcore you are. Because then you will want to buy more controllers, games, network adapter, & wireless internet. To take advantage of it you will need a HD tv & a Dolby Stereo system.
I have owned 2 xboxes and bought and sold over 8 PS2 and never played any of them more than 30 hours total. What a waste for me.