Just the Wii. While I would like to have all three, I don't have the time to play them and can't justify the cost, so I just bought my favorite.
One disappointing thing I've noticed, though, is that almost all of my favorite games are from Nintendo (Mario Galaxy, Mario Strikers Charged, Metroid Prime 3, Excite Truck, Wii Sports). I'm still waiting for the mass onslaught of 3rd party games. Though I have to say, I really enjoy/ed Super Monkey Ball: Banana Blitz, and I'm really looking forward to BWii, Medal of Honor 2 (except it doesn't have multiplayer in the same house!!!! WTF!), and Guitar Hero 3. I promised people I wouldn't buy them so they had more Xmas options. Sigh . . . .