(UPDATE: There was a problem with 1.0b1. Please try 1.0b2, linked below, instead.)
I've just released a beta version of my first plugin for Movable Type 4.0: Bookmarks.
You can download 1.0b2, which has been tested with MT 4 Beta 4, here. There's no documentation yet, but it's fairly self-explanatory. When you're on any page in the MT CMS, you can bookmark it. Each author has their own set of bookmarks.
Here's the impetus for this plugin. On the ProNet mailing list, a number of people have expressed reservations about the thoroughly revamped navigation in MT 4. My feeling is that the new architecture represents a big usability improvement for two general categories of users: 1) the administrator who needs to manage dozens or even hundreds of blogs in an enterprise-scale installation, and 2) an author with a single blog, whether a blogger who's installed MT for himself or someone who's been provided with their own blog as part of a larger installation.
However, there's another type of user: a single author who creates and updates content on multiple blogs. Not an arbitrarily large number, but more than one. That describes me, for example: the MT installation that runs kshay.com and staggernation.com actually has 16 separate "blogs," some of which function as blogs and others that hold various pieces of content. With the Main Menu in previous versions of MT, it was easy to create a new entry, or view entries, templates, etc., in any blog with a single click. In MT 4, having first to switch to the intended blog, then click on the desired action, feels like a step backward in terms of usability.
The Bookmarks plugin is intended to restore some of that ease of navigation, especially for someone who authors multiple blogs.
Please post all comments, bug reports, and feature requests concerning Bookmarks to this area of my plugin forums.