Well will you look at this. Someone has grabbed a screenshot that clearly shows Jet Set Radio as a game that is on Xbox LIVE Arcade.
If this is real it's a great boon for those who haven't played Jet Set Radio. Getting the game would not only let you play one of the best games on the Dreamcast in HD, but also could show SEGA that the gaming community would support another Jet Set game. How do I know we would? Because I will personally hold a gun to every gamer's head until they buy it.
Of course I have probably jumped the gun a bit here. I'm already planning to threaten the lives of millions over the re-release of a game based on a shot that could be fake.