I think my favorite sessions at this year's TechEd were John R Durant's sessions on programming Office using the new Visual Studio Tools for Office.
John is a very entertaining speaker and is very passionate about the VSTO tools. I loved his session on Outlook where he demonstrated creating an Outlook add-in. It's very easy to extend the functionality of outlook using these tools. I can see a lot of good uses for this.
For example, a company may use email for its business, and one of its needs is to save email messages to certain folders on a file share. The folders are related to the type of email and the customer. Using VSTO, I could easy create a menu item or toolbar button that runs some code to determine where the message should be saved, and save it.
Check out this MSDN article on working with tasks in Outlook. Very cool stuff.