K, the current system's are all good, different in few ways outside of libraries and look and controllers, as far as graphics and sound go. The choice of which one is better is based on opinion of game genre. Want FPSs, racing games, fighting games and sports games? Xbox should be your pick. RPGs, adventures, sports, fighting, racing? PS2. Adventures, puzzles, multiplayer party games? GCN. However, the PS2 has the greatest library of games, followed by the Xbox. The GCN is a sad state for Nintendo, despite some decent games.
Next generation's coming around. X360 is a great system, if you like online play, you'll LOVE Xbox Live. However few of the games have truly made the system worth it's money. Too Human does look potentially REALLY cool, and Halo 3 will only be fantastic if it finally finishes it's goddamned story. The gameplay has gotten damn old, and wasn't as spectacular as it's fame claims when it first came out. Microsoft's gonna need a stroke of luck to catch up to the other two farther down the road. It's shown a sad display so far.
The PS3 will be the most powerful system, hardware-wise. Also expensive, very expensive, if not more than the 360, at least as much. The library shows promise, and not just cuz of Capcom and Square-Enix support. It's backward compatibility to it's previous two systems is a help, too. However, they better lower prices or they're gonna fall hard. They really are full of shit when they say people will pay that much for their system and games. Yes, SOME people will. Most won't, especially not those who can't afford it in the first place.
The Wii (god, they should've gone with Revolution...) screams of potential and innovation. Still as controversial as Windwaker's look, everyone will eventually come around and realize that the decision to have a remote at the control is pure fricken genius. It includes the standard controller (the Shell) and adds a PLETHORA of new options and capabilities. Duck Hunt was awesome with it's gun. This is gonna blow that away, since the controller will have that capability and more by itself, nevermind with help. And the games down the line are exciting: Metroid Prime 3, a new Zelda, a new Mario that actually lives up to be a Mario 64 sequel (unlike disappointer Sunshine), possibly a Donkey Kong that isn't a retarded bongo DDR, a VERY exciting Smash Bros with free online play, Sega support (hopefully shitty sales and reviews will FINALLY get through to Sonic Team's heads and they're make a GOOD next-gen Sonic game), besides the promise of heavy third party support (everyone in the market is talking about how excited they are to work with the controller, EVERYONE). And full, legal backward compatible library, with possibly advancements. Plus it'll be smaller and cheaper, quite cheaper, and probably play DVDs (about fricken time). If Wii (*shiver*) isn't the obvious choice, than humanity really is dumber than I thought.
That's my take. Once I get the money, the Wii is mine. Once the price drops significantly, the PS3 is mine. Once I win the lottery or a random contest, the 360...may be mine.