I've been promoting this at the booth at Tech Ed but also wanted to make sure I mention it on my blog.
We're having a VSX Developer Conference at Microsoft on September 15th and 16th. It'll be a two day conference to go deep into developing extensions for Visual Studio, the VS shell, and DSL Tools. The conference is open to the public and is pretty cheap - $100. Compared to the price of Tech Ed, it's dirt cheap :)
For more information, visit http://msdn.com/vsx/conference
Sign up soon though as space is limited.
Hope to see you there.