I have a dim view on any sort of zealotry, and game console rivalries are a specially pointless kind of argument - mostly because it's about the games, not the number of ports on the box, the controller shape or the polygon fill rate. But since the ether is abuzz with Xbox360 and PS3 rivalry, I thought I'd jot down some thoughts.
I happen to own both previous incarnations of those things, and the only one that still gets fired up for actual gaming (ever since I got bored with Halo) is the PlayStation 2 - and not very much, at that. Pretty much every PlayStation game I've played is consistently better in gameplay than any Xbox title, and I've amassed a few PSX classics as well - good gameplay is timeless.
The Xbox has kept its place by being turned into a media center of sorts (thanks to XBMC), and I like to think of it as the first step towards my future home media archive - I envision a day when we can rip all our DVDs to H.264 (under fair use, before you go paranoid on me) as easily as we rip CDs to MP3/AAC. And that includes storing everything in a central (big) media server, download TV series from some sort of iTunes music store, the works.
(Of course the media industry will make a mess of this, but that's another story.)
The Xbox360 seems to be closest to that off the bat with its Media Center Extender features, but, again, the bottom line is about games. And if you take the trouble to hunt down the PS3 Killzone 2 video, you'll see that it is damn near close to Final Fantasy quality (at least the bits that we get to see).
I just hope it can be played properly - with a mouse and keyboard.