The point is, next generation graphics architectures will be introduced when TSMC's 20nm process is mature enough, that won't be until H2 of 2014, so Q3 the earliest with Q4 being more likely.
http://www.fudzilla.com/home/item/32578-20nm-high-performance-chips-in-2h-2014
If Nvidia releases Maxwell on 28nm (which they won't) as Videocardz speculates, it will only be a stop-gap solution between GK104 and GK110 since GK110 is the largest producible chip on 28nm, Nvidia simply can't make anything that's more powerful on the same node, any performance improvements will require additional die area and thus a new process node.
Nvidia won't make a stop-gap solution between GK104 and GK110 because it does not need to do so, it can simply use lower-binned GK110 dies to fill up any market gap.
They want to appeal to the mass market. That's why when a company strikes gold with a gaming formula (COD is the first one that comes to mind) they can milk it for ages.
Side Note: Below is a great (and funny) video based loosely on this topic. There is some language that may offend, just a heads up.
Khrass reacted to TechFan@ic in R9 280X vs TBD NVIDIA 800 series?
Khrass got a reaction from chinabrus in EVGA SLI Bridges are here!
Khrass got a reaction from Dragontail in Your opinion on why gaming has gotten easier
