Movable Type 4 introduces a whole new dashboard with the focal point being tracking the activity across your blogs. For my personal MT install, however, this isn't terribly useful (being the only author, I know my - albeit dismal - entry posting frequency, and I receive email notifications for all comments).
I much preferred Movable Type 3's dashboard which provided a list of all blogs in the installation with a few quick links. My Blogs adds a widget to your dashboard which allows just this.
Movable Type versions: 4.3