And they're also using Office. I saw the post over on TabletPCBuzz.
Here's their site. They're using OneNote for their project. So far it looks to be very, very early in the development cycle. Theirs will probably be a less expensive final product (they use OneNote and Access; I use InfoPath, SharePoint, and SQL Server). It's certainly nice to see that I'm not the only one investing in the Tablet PC platform.