Who says it's a kiddie system??? I'm an almost-40 year old, and I reckon the Wii is definitely worth it. I haven't touched my PS2 since the Wii arrived, and my 360 is gathering dust. Bored of the same old games coming out.
As for games... there seems to be a lot of people bagging it for lack of games... but honestly, it depends on what you want. Zelda was well worth it. And I'm currently playing The Godfather. MOH:Vanguard should be here tomorrow too. I also have Madden and Call Of Duty for it. Not to mention about a dozen Gamecube games that I can resort to if I want to play some soccer, etc. And then there's the VC games.. we're into Zelda OOT at the moment.
I'm happy with the games that are available. I don't have money to buy them all, so I choose carefully, and play them through. I don't play 8 hours a day, so they last me well.
The controls are GREAT!! They give a bit more immersion into a game, and I find them more comfortable to use than a 'traditional' controller.