As someone who shoots an APS-C camera, I'm really excited to hear this. Of course you can stick most pro lenses on most non-pro bodies, but you then run into the crop magnification and such. Canon it's 1.6x, I believe Nikon and Sony are 1.5x.
The price tag on this camera is likely to be pretty steep... which is my only hang up. Engadget is speculating over $2,000 USD.
This lens should be nothing short of a weapon of the night!