There are some new UI elements you might program for: Jump Lists, Thumbnail Toolbars, Overlay Icons and Progress Bars, Custom Switchers, Deskbands, and changes in Gadgets and Window Arranging. Nothing crucial or life-threatening though.

You can watch the webcast or just browse the PowerPoint deck: Integrate with the Windows 7 Desktop.

There is some new stuff "under the hood" too, some of which will be back-ported to Vista and XP in coming updates. Mostly stuff like a new native code Web Services API, Windows Installer enhancements, changes to default cryptographic hashes, UAC tweaks, etc.