Graphics don't mean anything in a game. I played through God Hand from start to finish just after I finished Okami and do you know what I had more fun in? No joke, I found God Hand more engaging than Okami! I think that's blasphemy. Neither of those games had particularly "good / flashy" graphics but both had unique styles, settings and gameplay which made them standout.
The point about tetris is a good one, as for PacMan and any other old school game, even Mario. As long as the graphics accomplish the task they're set out to, I'm all for it.
At the moment I'm absolutely hooked on CoD4 online both PC and Xbox 360. When i'm gaming on my PC, the resolution is set to 600 x 800 and the textures are at their lowest. Playing the 360, I'm treated to wonderful, clean and hi-resolution images but the game remains the same. In fact, I prefer playing CoD4 on my PC and it looks like a last generation Doom game!
As long as I'm having fun, I don't care.