Version 3 of Groove is almost ready - it's in beta test. The development organization here has been firing on all cylinders for a long while, and finally the marketing guys started talking about the upcoming version. I'll restrain myself to the occasional comment, because most recently I've been focused on applications for the 2.5 servers more than on the V3 code (although that'll doubtless change).

Even if you don't follow all the weblogs, here's one must-read article today. Steve Gillmor at eWeek has taken a look at V3, and thinks GFS is the killer app:

Performance has been improved by a factor of 2, 4 or in some cases 10. But a new feature, GFS (Groove File Sharing), is perhaps the tail that will wag the dog.
...Now, with the ability to synchronize files directly from the Windows file system across Groove's secure XML network, users can share documents in the context they're already comfortable working in: Windows Explorer.