Although it doesn't matter anymore, there are several bits of evidence supporting the theory that NVIDIA originally intended for its GK104-based performance graphics card to be named "GeForce GTX 670 Ti", before deciding to go with "GeForce GTX 680" towards the end. With the advent of 2012, we've had our industry sources refer to the part as "GTX 670 Ti".
What's in the name? Well for one, naming it "GTX 680" instead of "GTX 670 Ti", releases pressure off NVIDIA to introduce a part based on its "big chip" based on the GeForce Kepler architecture (GK1x0). It could also save NVIDIA tons of R&D costs for its GTX 700 series, because it can brand GK1x0 in the GTX 700 series, and invest relatively less, on a dual-GK104 graphics card to ward off the threat of Radeon HD 7990 "New Zealand", and save (read: sandbag) GK1x0 for AMD's next-generation Sea Islands family based on "Enhanced Graphics CoreNext" architecture, slated for later this year, if all goes well. Is it a case of mistaken identity? Overanalysis on our part? Or is there something they don't want you to know™?