That's a tough one; my knee-jerk reaction is an emphatic, "No!" but then I think about all those times I was genuinely mesmerized by screenshots and demo-reels and I have to kick myself upon the realization that, "I fell for it." Then again, I feel vindicated by the fact that so far the best-selling game consoles have not been the graphical powerhouses (with the possible exception of the first Playstation and the Dreamcast).
Sometimes, the high graphics are welcome, and there are genres and gameplay styles that genuinely benefit from the technological advancements. Take the Thief series, or any stealth game for that matter, and we'll find that without the breakthrough of dynamic lighting (and the concealing shadows they create), the game would be a totally different experience (probably less fun). It's the same with racing games; Mariokart and Wipeout are great, but when I want the true sensation of speed and power, I'll always turn to Enthusia or even Outrun 2006. RPGs seem to be the only truly 'graphics-proof' genre; Paper Mario is every bit as rich and detailed as any Final Fantasy game despite its deliberately simplistic graphical style.
Graphics will get the games off the shelves (and mostly into the hands of the casual gamers), but it's the gameplay that's going to keep them out of the 'used' bin.
