Get the game for GC, but buy a Wii for: SSBB, Metroid Prime 3, New Super Paper Mario, Mario Galaxy, LCT, Mario Kart Wii, and of course in anticipation of the next Zelda title. Add in some supposedly decent third party games down the road.. (like a new FFCC) and you can see cause to get a wii.

Still, the GC version, in my opinion, is better then the Wii version for TP, despite the major "differences" being minimal.