Spent some time with the Wii today.
And spent time in Nintendo's booth at E3.
Anywho, long story short, the Wii and it's Wii-mote is a gimmicky ridden controller with a last gen graphics game system at it's core.
Played primarily with the Tennis game, Metroid, and Warioware. The tennis game is crap. The player is automatically controlled, and you only control the swing, and it doesn't matter how or where you swing, it's all timing based, you might as well just press a button. If you are trying to actually swing like you are swinging a rachet and playing tennis, you are just looking like a fool and pretending, because, guess what? The Wii is not tracking any movement other than just the swing timing.
Metroid. The Nunchuk controller setup is crap as well. Any seasoned FPS player (I've played from PC to console FPS's) will get over the novelty of the Wii-mote in about 30 seconds, and realize there is no way to properly circle strafe, and that turning around it is actually SLOWER than with dual stick controls (and I don't like the dual stick console FPS gaming controls, but can do it). Looking around is controlled by moving the cursor to the edges of the screen, "WASD" movement is controlled by the Nunchuk's analog stick. This game might as well be on rails, and be a House of the Dead light gun type game. Oh, and the Wii-mote requires a Sensor bar taped/velcro'd/glued to the TV or near it in order to work. It needs line of sight, and easily goes off course if you are not in the right "zone", so all those ads of people moving all over the place is utter lies, because no line of sight = no workie.
The Wii is cute from an industrial design standpoint, but it does not have much substance on the insides. Nintendo will gain new "casual gamers" and yound kids, but they will start to alienate other gamers, particulary hardcore gamers. If the Wii is priced over $200, they are going to have problems.