Better in every way.
this game is a magnificent achievement. in addition to improving on the original in almost every single way thinkable, bungie has added an online infrastructure that set the bar for xbox live on the 360.
the graphics are amazing, the gameplay is akin to a space-themed shooter, but is polished and refined to oblivion. there are a quite a few glitches with the multiplayer but they are all really fun. for instance, i spent many more hours getting out of maps and exploring glitches and secrets than actually playing legitimate games.