The day didn't start to well... on my commute from my hotel to the Microsoft campus someone hit the rental car I was driving, so I spent the majority of the morning taking care of that. I missed the morning keynote that dug more into SOA and was basically the second half of the Pat Helland's presentation. Luckily I had seen most of that back in August when he was working on the initial draft.
I arrived at the conference center just before an informative session on writing client applications on the Longhorn platform using some of the new stacks (Avalon, Indigo, WinFS). Although this is a long way off, there was some pretty neat UI demonstrated. I was also interested in the fact that Longhorn will be fully managed and allow for complete access to the OS. The advantages that we see now in the unified BCL are the same that we will see when the OS becomes managed.