I'm not talking about a system's capabilities, I'm talking about scoring the game based on the way it was intended to look. If Capcom had said, "We want MM9 to look like Bionic Commando: Rearmed", and then delivered the game with NES graphics, then by all means give it a 3.0. But when Capcom openly says, "We're going to go retro and make this look and play exactly like the NES originals", why not reset your baseline and compare its graphics to the NES originals that it's designed to emulate?
Mega Man 9 is essentially a new NES game. That's what it was intended to be all along, no more, no less. I think it should be held to the highest standards among NES games, not the highest standards of the current generation of consoles. Mega Man 9 is an interesting case, though; it's likely the first brand-new game released on a current hardware platform that's deliberately designed to look like it's on an early platform. It's a "dream scenario" kind of product that hasn't required classification before.