Microsoft’s mystery touch device is actually a competitor to Apple’s Magic Mouse. A store listing points to the Arc Touch Mouse touch surface. It was originally the result of a research project called Mouse 2.0, that looked into an multi-touch mouse whose details were published just before Apple shipped the Magic Mouse.
The controller was originally designed to provide multi-touch to Windows 7 computers that don’t already have a touchscreen. It should cost about $70 and should arrive in stores by September.