There's lots of details in this WebRidesTV video from SEMA 2007, from a great look at the Five Axis Project IS-F to Scott Pruett's demonstration of IS-F with VDIM on/off:

Looks like the IS-F's release date is firming up. Brian Bolain, the Lexus national advertising and media manager, reveals that the car should hit the dealerships in March 2008.