Mix 08 is well underway right now. If you haven't been following the news coming out of Mix, there sure has been a lot of it!
Check visitmix.com for the latest info.
Lots of great talks posted in the Open Space area here at Mix. You can see the schedule at http://www.visitmix.com/openspace Many of these being recorded and posted up on the site afterwards.
[Update:] You can find the Open Space videos here: http://visitmix.com/blogs/openspace/
Here's the current list as of now: