Framerate absolutely matters for gameplay. That's why Call of Duty's controls are so highly praised, because it's one of the few shooters at 60 FPS. That's why Metal Gear Rising worked better than DmC last year, because action games like that almost need 60 FPS. It matters less for AC, but the gameplay absolutely is better at 60 FPS. It's just a matter of smoother, more fluid controls.
As for resolution, what you say is true, but beside the point. If Ubisoft just said their game was going to be 900p, there wouldn't be an issue. But they were one of the developers talking about how much graphics matter, how resolution matters, and all that stuff. So for them to say it doesn't now that giving the best image quality isn't convenient for them, yeah that's bullshit.
