Just some of the great speakers I've heard:

Michael Rhys, on XQuery

Yasser Shahoud, on Indigo (now called Windows Communications Foundation)

Paul Vick, on advances in Visual Basic

Just a note for all you Visual Basic developers...make sure you let Microsoft know that you're out there and the things you like/don't like about the language. The predominance of folks are C#/C++, according to some MS insiders, and we need to make our voice heard if we are to get the respect that Visual Basic deserves!