Spot on, or a few FPS depending on which game. AMD or nVidia fanboys can both produce statistics favouring their love.
In my mind 'mantle' was what I thought was going to be a game changer but seeing that AMD have confirmed its a PC only API, its just a niche option and not essential.
I think i've made myself clear that I don't buy into all the RAM propaganda, but the major consideration would be the drivers. Games will mainly be made for consoles (its where the money is) and the ports will be a hell of a lot better than the last five years. With AMD powering the consoles I would expect the drivers to be, lets say easier for AMD hardware on the PC (optimisation), meaning nVidia will likely more of the time have to play catchup with new games, (edit) Other than games they partner with.