I went to Nintendo Fusion Tour yesterday (For the Wii, not the emo music) and got to demo 4 games (In order); Wii Sports: Tennis, WarioWare, Wii Sports: Baseball, and Wii Shooting.
Tennis was pretty lame, I didn't like the fact that when you moved the wii-mote, the tennis racket didn't move. It made timing your swings a bit difficult, and seemed kind of off.
WarioWare was amazing. Seemed extremely precise, and just plain fun. The most akward thing about it was pushing the wii-mote forward to insert the dentures into the person's mouth. Not in a bad way, just felt weird.
Baseball was probably my favorite, I never liked sports games, but the Wii just may change this. Every single movement you made with the Wii-mote, so did your characters bat. If you swing a bit upward, the ball flies higher, if you swing slightly downward, the ball hits the ground and bounces. The only thing i had trouble doing was trying to bunt the ball, I tried 3 times, and failed. The funny thing was, the guy that was working there looked at me and said "You have to swing it", after I played for about 5 minutes when I tried to bunt the ball.
Wii Shooting I picked up extremely fast. I watched 4 people play it, and [brag] I almost doubled their score [/brag] The controller seems extremely sensitive, but I got used to it pretty fast. It might take a while for most people (including myself) to get fully used to the sensitivity, although I'm sure you'll be able to change it.
So that's it, I had my 15 minutes of what seemed like a dream, I was so excited I barely remember it, haha. I just figured I'd share my experience with you all (and brag that I got to play the Wii before millions of people a bit).