SEA OTTER: Singletrack.com showed you Shimano's new 10-speed drivetrain last week. Here's a video view of the new group from Sea Otter.
The question was not "if," but "when" and "how" Shimano would go about creating a 10-speed mountain bike drivetrain. Now those questions
Shimano Dyna-Sys 10 speed mountain bike drivetrain gallery