This is a maintenance release free to everyone with a valid Teamprise 3.0 license and includes several bug fixes along with a few new features. For the proper release notes, take a look here. However I just wanted to point out a few highlights.
Improved Offline Support
With-out doubt, the biggest new feature in Teamprise 3.1 for most people will be the improved offline support. If you right click on a project in the Eclipse IDE, you are now presented with a "Go Offline" option which allows you to tell Teamprise not to bother trying to talk to TFS for a while (previously you had to restart Eclipse for Teamprise to ask you if you wanted to go offline, and only then after it had tried *really* hard to connect).
While offline, you can still perform all the file operations like you expect -- you can add, edit, move and delete files just like if you were online.
When you want to come back online (say when you have stepped back out of the plane, bus, meeting room), you can right click on the project and say "Return Online" and Teamprise will do it's best to detect what changes have happened while you were away, giving you the option to pend those changes.
There is even "return online" capability in the stand-alone client Teamprise Explorer which is very neat and makes working with tools that are not TFS aware a little easier too. The actual algorithm used by the return online feature is more sophisticated than just checking for read/write status in your local workspace, we also do some magic and compare checksums of the file contents etc. Fellow Teamprise blogger Ed Thomson was the lead developer for the offline work and he has some more details on his blog.
For detailed release features please check it on Martin Woodward Blog address below