My roommate just picked one up. I am not really a video gamer (stopped at n64) but this thing is pretty awesome. From what I can tell the xbox and the ps3 are all super graphics super powerful blah blah but they really aren't as fun as fucking wii tennis with the motion senso nunchuck.
The graphics (i've seen so far) are pretty crude, the resolution seems standard, but damn it is a lot of fun. playing xbox 360 was not as fun as the wii. In my opinion the controller is the next step for video games, not the graphics. As long as we're still pushing puttons and moving a mini joy stick the games can't improve that much.
the wii is going in the right direction, there are so many cool things you can do with that little wand. I feel like with xbox and ps3 we're just going to get the same types of games, just better graphics and online integration or whatever.