Major Xbox 360 announcement at BlizzCon?

UPDATE: No 360 announcements after all? GameSpot says it's all about Vista OS... [Thanks to everyone that sent this in]

Gaming Steve has raised some interesting questions about Microsoft's involvement in BlizzCon this Friday. What will be the topic of choice during the hour-long "Microsoft Next Gen Platform" presentation? Our gut tells us
StarCraft:
Ghost; our hope is for an Xbox 360 version of WoW. But Gaming Steve has just confirmed that Greg Canessa, the group manager of Xbox Live Arcade, will be present. Could a big announcement be in the works? Perhaps a surprise revival from Blizzard's past...