Wii gets my vote right now, due to Zelda and the at-home multiplayer (I've grown to hate online video games anymore) of the other games
However, I still play my PS2 more than I do my Wii, due to the fact that the PS2 library has tons of great RPGs with good replay value. Once the good RPGs hit the PS3 (FFXIII, KH3, etc), I'll probably make the PS3 purchase and be playing that one more, until another Zelda comes out on the Wii