Six Apart today released the Movable Type 4.0 Beta. It offers a lot of new features, including a much more Ajax-ified interface. Whereas Movable Type 3.0 simply added a much more streamlined css stylesheet to the interface, in 4.0, I actually feel like I need to relearn the interface.
Looking at the known issues is disheartening, as I'd guess at about 3 months worth of work to fix all the items.
Every revision of MT adds more bloat to the default templates, and 4 is no exception. At first glance, it seems as if the templates have gotten more effficient, more concise, but this is misleading -- the templates are now broken down in subsections such as Header, Footer, Entry, and within those sections they're further broken down into sections like Sidebar, Tags, and Entry Metadata... This makes modifying a particular section easier, but I haven't yet figured out how to add these subsections to older template files.
Also, Movable Type 4.0 seems to really dislike the MTCategories tag within older version RSS templates.
Hi, you're quite right in your estimate for the beta. I believe Six Apart intend to wrap it up within 6-12 weeks...