Yea that's the Antonov two speed supercharger system. The basic concept is that they've mated a Rotrex Supercharger to a two speed automatic transmission which results in a claimed 85 percent efficiency, versus roughly 50 percent in a traditional supercharger.
The Antonov transmission also has other possibilities such as being mated to an alternator to increase alternator speed at low engine rpms, and reduced alternator speeds (thus reducing drag) at higher engine rpms.
According to Autoblog
"In a Mustang GT application, Autonov was able to "hide" the compact supercharger/drive unit under the intake manifold." which I guess is what we're seeing in the pictures
on that website.
Pricing for this system is said to be $5,500-$7,400 although I'm not sure how available it is at this time.
http://www.autoblog.com/2006/05/05/big- ... ercharger/