Last December I thought the idea of an AddOn Studio for WoW was amazing. And if you missed the Ken Levy interview about VSX on .Net Rocks then make sure you give that a listen – he goes in to a few details about it. What’s this got to do with VSX? The main thing is that the Wow AddOn Studio is its own standalone IDE built with VSX (here’s a brief overview of VSX if you’re interested) using the Visual Studio Shell.
BTW good luck to Ken on his new gig – he’s running his own show called MashupX now.
As Dan Fernandez notes, the WoW AddOn Studio V2 Beta is up on Codeplex.