The UMPC Community --http://www.umpc.com/
UMPC Community website where enthusiasts could share their thoughts, ideas and comments around this exciting category and the opportunities it creates for users, developers, and customers.
Intel: Ultra Mobile PC (UMPC) --http://www.intel.com/go/umpc/
The Ultra Mobile PC (UMPC) category offers consumers small, ultra-mobile devices with full PC capabilities, uncompromised Internet access, anytime connectivity, and the ability to recognize and adapt to its environment virtually anytime and anywhere.
Microsoft MSDN: Announcing the Ultra-Mobile PC --http://msdn.microsoft.com/mobility/tabletpc/umpc/default.aspx
: The ultra-mobile PC (UMPC) is a device-like computer that is small, mobile, and runs the full Windows operating system (currently Windows XP Tablet PC Edition 2005 and soon Windows Vista). The UMPC goes anywhere and does anything that your current computer can do. The UMPC accomplishes what many and varied portable devices do today, but because it runs the full Windows XP operating system, the UMPC does everything your desktop computer can.