Well, the first obvious choice is Zelda: Twilight Princess. The environments are beautiful, the dungeons are puzzling and you'll be playing a long time since there's so much to discover.

WarioWare: Smooth Moves is a very fun game which really puts the Wiimote in focus. You'll probably have most things unlocked within 2 days if you're good, but it's still a nice game to play every once in a while. Especially if you have friends invited over to your house.

Excite Truck is, as far as I know, the most satisfying racing game on Wii so far. You hold the controller sideways and rotate it just like a steering wheel. Speaking of which, I recommend getting Joytech's steering wheel accessory for this game and any future racing games. It's a little on the short side and doesn't offer that many levels, but it's very addicting and has a lot of unlockable trucks that you can choose from.

The problem is that a lot of third party developers don't seem to have a good imagination. They're basically taking already existing concepts and slapping motion control onto it. They care more about how much money they can make rather than innovating and breaking new ground. Instead of asking themselves "How can we make our old ideas seem more fun and exciting?" they need to ask "How can we come up with completely new playing styles that weren't possible before, and add a new level of fun and excitement?". Somehow I get the feeling that Nintendo weren't clear enough when they tried to convey their message of what Wii should be.

Here, how about a nice and simple list:

• It's cheap.
• It's compact.
• More power-efficient than its competitors.
• Innovative control (swing it like a tennis racket, point it at the screen as a gun, rotate it like a steering wheel).
• Very durable controller, trust me. Just don't go trying anything now :)
  
• Guaranteed success at parties :)
  
• The controller's simple rectangular shape makes it very easy for companies to create shells for it, such as the steering wheel (a must for racing games). I even made my own gun shell for it out of cardboard.
  
• It's already starting a revolution in Flash-gaming as people have figured out how to use the buttons on the Wiimote to make it act like a NES-controller.
• Download c|assic titles through Virtual Console.
• Communication with Nintendo DS via Wi-Fi (the upcoming Pokemon title will be the first game to use this, and I see many interesting possibilites in the future).