Intel is supposedly developing a new UMPC platform according to some slides seen by the folks at HKEPC.  Engadget has posted some pics and information on the subject including a smaller footprint and doubling of current UMPC battery life.
Known only by its codename “McCaslin,” the chipset will reportedly occupy a space of 975 square millimeters (as opposed to the relatively enormous 2915 square millimeters of today’s models) and feature power-sipping 600MHz and 800MHz processors known as “Stealey” that are targeting four to five hours of run time. Also sporting additional comm ports for devices such as GPS, 3G, and DTV, McCaslin is said to be Intel’s response to Via’s small form factor C7M,