The 120-300mm f/2.8 DG OS HSM lens is part of the Sports line-up, has Optical Stabilization, a Hyper Sonic Motor, and a new weather sealing. The lens does not extend when focusing or for zoom. No information about the price so far, the lens with Canon mount should be available next month.
The 17-70mm f/2.8-4 DC MACRO OS HSM is part of the Contemporary line-up. It is said to be smaller by 30% than comparable lenses. It features low dispersion glass elements and a special low dispersion element. No pricing so far, the lens for Canon mount should be available this month.