There's potential for the Wiimote to do more than a mouse. You can twist the Wiimote and it can turn something on-screen. You can also move the Wiimote forward and backward to move something from the foreground to the background. Thing is since the PC doesn't use any games as far as I know that actually take advantage of it it's pretty much useless except maybe in the freeware community where people can make games specific to the Wiimote.

If you play Metroid Prime 3 you'll see some of the stuff they've put into that game. Some of the twisting puzzles, moving objects back and forth, etc. Actually, foreground and background moving has been a little annoying in that game, though. Maybe it's where I'm sitting while playing the game but I find myself having to repeat pulling the energy tank out of the wall before it successfully works for some reason.