One of the many Visual Studio 2005 features announced at Tech Ed today is the Class Designer.  See here for details and screen shots.  Not counting all of the mobile-specific stuff in Whidbey, this is the the feature I'm personally looking forward to the most.   A big chunk of my job involves designing and reviewing new managed APIs so I've been using VS 2005's Class Designer a lot lately.  It's made life much more pleasant for getting a holistic view of things, refactoring, and driving design discussions.  This isn't fully hooked up for .NET Compact Framework projects yet but Amit tells me that this will be taken care of.  If you have a community tech preview of VS 2005, be sure to install it and check this out.

[Author: Robert Levy]