As for a release date, a post by a Microsoft employee on a job profile on LinkedIn suggests Office 15 is scheduled to ship in 2013.
As far as tea leaves go, those aren't particularly definitive, but they certainly seem to point in a consistent direction: better collaboration, more emphasis on mobile access, and expanded Outlook connectivity. It sounds like a brave new world, indeed -- only three years to go.
This article, "Tantalizing details emerge about Microsoft Office 15," was originally published at InfoWorld.com. Get the first word on what the important tech news really means with the InfoWorld Tech Watch blog.