Honestly, I don't think they are. I appreciate good graphics, but if I have enough time to sit and look at the environments while I'm playing, then the gameplay clearly isn't engaging enough (depending on the genre of course - an RPG would be excused in that sense). Besides, the improvements haven't been that noticeable between PS4 and PS3, at least from what I've seen. The launch titles look slightly better than the best looking games of the last generation, but that's what you'd expect. Even the Wii U has games that look slightly better than last gen titles.
I dunno, maybe I'm different to most people when it comes to graphics, but I'd much rather developers focused on gameplay over graphics. Taking into account how many companies are struggling to make money, it doesn't seem like a worthwhile investment to focus huge portions of the budget on ever so slightly improving the graphics.
I'm not saying that a new console shouldn't be more powerful - of course it should - but people are expecting far too much from them. I think it could put both Sony and Microsoft in a tight situation a few years down the line. If they continue to try and one-up each other, they're going to reach a point where the consoles are far too expensive for the average consumer, and far too expensive to develop for. While Nintendo are far from competing in terms of power with the Wii U, it's at least sustainable in the long run. While a part of me is excited to see what can be done this generation, I'm also worried about the consequences of pushing for power.