Microsoft Research works on Boku, a stimulating game that introduces kids to programming while they play. Through programming Boku, a virtual robot, children learn the basic principles of programming logic, analysis, and design.
It is never too early to scout the next generation of Microsofties.

The 3-D interactive game is designed to demystify programming and to spark interest in science. Boku is currently trailed on selected kids. The Boku programming environment runs on the XBox 360 and Windows PCs, allowing rapid design iteration using only a game controller for input.
Boku is still a Microsoft Research Project, but I can imagine Microsoft releasing Boku soon.
Via the Boku site.