I don't think it's the first time it's been done in consoles, I'm pretty sure the original SSX had playback that you could save on the PS2, I'll have to dig it out to confirm though (man I loved that game).
Anyway, I don't think the playback itself is that innovative, but the fact that you can run the playback and everyone in your party can see it as well from whatever view they want, you can upload it to your fileshare for anyone else to download, and even take your own snapshots that automatically get uploaded to bungies website for you to do whatever you want with. It's just very well done and seamlessly integrated into the game and the community, I think that's what makes it innovative. Kinda like the way we say the wii is innovative, even though the wiimote wasn't the first motion contoller.
Currently Playing: Saints Row 2 | Battlefield 2 | Company of Heroes
Recently Beaten: Gears of War | Super Mario Galaxy | Darwinia | MGS4 | Sam and Max Ep. 4, Portal | Mirror's Edge | Uncharted | Mass Effect
Looking Forward to: Alan Wake | Splinter Cell : Conviction | The Last Guardian | Batman: Arkham Asylum | SMG2 | Mass Effect 2 |
