So you weren't at MIX this year. For the MS community, the most important thing to be aware of is the fact that IE 8 was released to the public, whether you are ready for it or not.
But the highlight of MIX '09 has to be the video that they showed this morning called "A Brief History of the Web" which should be watched by all at:
http://www.microsoft.com/windows/internet-explorer/nethistory/