I've updated MIDI File Mapper to a new version, which is mainly a bug-fix release. I'm building it now with Visual Studio 2008 beta 2, which is looking much more like a finished product than beta 1. I'm still building against .NET 2.0 of course. The multi-targetting feature in VS2008 is superb.
I'm also trying to add unit tests whenever I do a bugfix. MIDI File Mapper is one of those rare projects that lends itself really well to unit testing. I still can't bring myself to go the whole TDD approach though. Mads Kristensen has some good thoughts about when to unit test which I think gets the balance about right.