Movable Type 4.0 has been released since a while. This is about the fourth version I install/upgrade to and I must admit all in all it works pretty well. I destroyed my blog when changing the templates, but with a backup at hand and a working importing function, I recovered in … sort of … no time.
So far the new version has a new interface, a couple of new fancy features, but most noticeably a very smooth editor. Makes blogging even more fun!