Here is a summary or excerpt from an article that has just been published on DPNow:
Canon Inc. announced today the development of Hybrid Image Stabilizer (IS), the world’s first* optical Image Stabilizer which compensates for both angular camera shake and shift camera shake.
Looks like Canon have been pre-empted by Pentax who have already introduced rotational stabilisation in their recently introduced K7 Dslr which is already on the market. Canon have been caught with their trousers down and are now trying to do a catchup.