In further confirmation of VR-Zone's findings with the upcoming 180.10 ForceWare drivers, multi-monitor support when in SLi is a definitive addition. NVIDIA has just spilled the beans on what the new driver (referred to as the 'Big Bang II' some time ago) will bring to the masses. From what we now know, it's quite the milestone for the company and should live up to the hype.
Both Tech Report and PC Perspective have covered the upcoming driver in detail. They've learned that there are four major features coming; the aforementioned multi-display mode even when in SLi, significant performance increases across a wide range of gaming titles, the ability to assign a GPU purely to PhysX computations and last but not least, the enabling of SLi support for Intels upcoming X58 motherboards for Core i7.
PC Perspective also posted some charts supplied by NVIDIA which compares performance across various popular gaming titles between the 178.xx drivers and 180s; it's a little vague but it is clear they are claiming a massive boost when making the switch.
The final WHQL release is due in the coming weeks; we'll be sure to let you know when it's ready.