I have been thinking about the Wii and everything we know about it. The Channels, VC, games and the Mii´s.
Mii´s, small blocky characters that you create that looks like yourself, your family, your friends and whoever you want to create (I bet that Reggie and Miyamoto will be created by thousands of players). So what are they exactly used for?
A first thought is that they are like the Sims in the game with the same game... just without the game. They are used as avatars in Wii Sports, so you can see yourself play tennis on the screen. Customable characters are not something new in games, you have always had the possibility to create a custom skater in the Tony Hawk games. But you had to do it in every game, and we all know how lazy some people are ;)
Sure they added more crazy looks and clothes in every new game, but still...
You can download your Mii´s into your Wiimote and infect your friends Wii with your Mii´s. Perfect for lazy people that are too lazy to recreate himself at a friend.
So what other games will use Mii´s? Wii Sport will use them. And WarioWare Smooth Moves will use them in an unknown way. Some games will probably use your Mii as a cameo somewhere. Think how fun it would be to discover your Mii´s in the background of Super Smash Brothers Brawl, cheering on the fight. Or seeing your Mii as a doll in Zelda TP. Endless possibilities exists if the developers want to use it.
Going back to the Tony Hawk custom character thing. How fun would´nt it be if you could use your Mii data to create a custom character directly, instead of you making it in the game? Sure, the Mii would look misplaced in most games, but let´s think a step ahead. It could read the height from the Mii, and it could create a texture based on the facedata so it looked better placed in the game, and it could give the character a standard outfit. Tadaa, and we have a Mii-based character that does not look misplaced in the game. This, my friends, gives us even more endless possibilities. Some FPS can create yourself as the main character automatically, or making yourself as a hidden boss in the game. Some shopseller in Zelda can be based on your Mii, or a secret character in SSBB will be your Mii. I´m only waiting for EA to give the thumb up for a Wii Sims that uses Mii´s.
And since the Wii can update itself, it´s a possibility that we will get even more parts to build our Mii´s with.
...as long as the games that uses Mii´s as a base takes that in count so it does´nt crash when you try to load a Mii with parts that´s unknown for the game ;)

Anyway, Mii´s will be big, no matter if games includes them or not. People will post guides on how to create their favoutrite characters in 12 easy steps. Some people want celebrities, some want gaming characters and some just want crazy-looking Mii´s. Let´s hope the gaming developers discovers the possibilities.