I've played with a friends 360, and on another friends PS3, never touched a wii.
I've owned a PSX, PS2, SNES, Original Gameboy, GBA SP,
Of the three new systems, I'd prefer a PS3 for gaming, a 360 for the Free60 softmod, and a wii for nothing at all.
If I could have anything right now, it's to have my old Snes back, and all my games.
(or maybe my PSX, and... games, etc.)
But at the end of the day, I'd rather just spend my money fixing/upgrading my PC...