If you didn't attend TechEd IT Forum this year, it's worth knowing you can see a number of sessions from this years conference online through ITs Showtime.

For Virtualization:

There's quite a few others including Windows Vista Kernel Changes and Advanced Windows Troubleshooting with Sysinternals Process Monitor both by Mark Russinovich which I also highly recommend.

The full list of sessions available is here.
Cheers,
John.