That seems likely. In fact, now that you mention it, I think I remember them saying on Facebook that it was a GSX-S. I didn't realize there was such a thing--I thought it was a typo.
Wikipedia describes the GSX-S1000 as "essentially 2005-2008's GSX-R1000 with some re-tunes for more torque."
It's listed as having 150 HP and 79.6 ft-lbf of torque at 9,500 rpm. Redline at 11,300 rpm.
--Greg