As Matt mentioned, we decided to delay the 2.2 release from its original date of April 23. We weren’t completely happy with the underlying design of the new tagging feature. Instead of shipping with something we weren’t entirely pleased with, we decided to remove tagging from 2.2. This is a big bummer since tagging was the biggest user-visible feature in 2.2. I think removing it was for the best, however, because the debate over the removal resulted in a new generic taxonomy design that is flexible and powerful and addresses all of the concerns with the old design. Plugins will be able to do some cool things with this new framework.
With the loss of a major feature, 2.2 won’t be as snazzy as we had hoped, but it will contain many bug fixes, lots of polish, and lots of hard work. Download the release candidate and check it out. If you need support for the release candidate, the Testers List is the best place to go.