I'm also intrested to know if nvidia has dropped the requirement for all monitors to have the same the sync polarity for 2d surround. Based on nvidia articles I've found, they only briefly mention monitor requirements.
www.geforce.com/whats-new/articles/nvidia-surround-on-the-geforce-gtx-680/#1
"Any combination of connectors and monitors is A-OK in 2D Surround, though in 3D Vision Surround the two DVI connectors and single DisplayPort connector must be utilized, and users must have three matching 3D Vision monitors."
http://www.geforce.com/optimize/guides/how-to-correctly-configure-geforce-gtx-680-surround/#1
"In 2D Surround, any combination of monitors that share common timings is perfectly acceptable, though each must have, at minimum, one DVI, HDMI, or DisplayPort connector. Aesthetically, identical monitors are preferable, but not a requirement."
Not enough to confirm it, but hopefully nvidia will update their surround
spec sheet with the GTX 680 shortly.