Let's start with the good news. According to Fudzilla, Nvidia is definitely planning to release a dual-GPU videocard, and relatively soon. Ready for the bad? It won't ship in time for the holiday shopping season.
Citing "sources close to the company," Fudzilla says Nvidia wants to wait for AMD's dual-GPU Antilles Radeon HD 6990 before releasing its own dual-chip videocard. Nvidia already owns the single-GPU performance crown (GeForce GTX 580) and wants to go after the dual-GPU crown as well, but is reluctant to do so before knowing what AMD's upcoming part will be capable of, Fudzilla suggests.
The GTX 590, as it's rumored to be card, will almost certainly be faster than AMD's current flagship part, the HD 5970. But if it's not faster than the Radeon HD 6990, Nvidia may opt to tweak the design until it's certain it has the best performing videocard on the planet.
No, this really long card isn't an actual prototype, just a quick and dirty mockup.