LOS ANGELES -- Look at the happy smiles that Wii Music puts on people's faces!

I swear I didn't mean to, it's just impossible to not laugh as you're hitting drums by shaking your hands like an idiot while somebody is playing air guitar with a Wiimote next to you.

Wii Music is one of the titles that Nintendo talked up at its press conference Tuesday. While we weren't quite sure exactly how it was played before today, we finally have some details now: Rather than challenging players to keep a rhythm or play the correct notes, it's a four-player, free-for-all jam that doesn't penalize anyone for messing up. So it's more like "play," less like a "game."

Does it work? From my hands-on time, it was certainly fun, but I don't know if this particular mode of the game will appeal to serious music gamers. Fortunately, there's a few more modes that look interesting.

The jam mode, shown above, will include over sixty different instruments, each of which is played by using the Wii remote in a different way. I tried playing the trumpet (center), which is the lead