I just spotted that the keynotes from Mix are now available online at http://blog.mix06.com/virtualmix/archive/2006/04/07/2354.aspx

It includes the keynotes from both Bill and Dean Hachamovitch the General Manager of IE. It looks like the link to Dean's keynote takes you to a single recording of both Bill and Dean's keynotes starting with Bill. They are both worth watching in my opinion.