I find it funny how everyone ranks the X Box higher than the other two. I personally see the X Box as a powerful system ruined by shitty games. Halo? Bah, hardly anything extra than your average FPS. What else has the X Box got that the other two consoles don't?
Only nod I'll give to the X-Box is that MP is generally better due to them only allowing broadband connections.

The GC's got some pretty good games. Personally, I can't stand Wind Waker (the graphics make me want to stab my eyes out with a toothpick), but I liked Eternal Darkness, Mario, Smash Brothers, Metroid and a couple others exclusive to the console. I really think Nintendo should go the way of Sega and just develop games. It's what they're best at.

The PS2's the weakest system hardware-wise, but they seem to have the best game developers on their side. I bought a PS2 simply because Squaresoft was only developing games for Sony at the time.