It's amazing to me how much we still sell from our "retro corner" at the back of the store. I'd have to say that it's pretty close to being a 1:1 ratio between customers coming in to ask about the PS3/Wii, and the 30-somethings who want the NES cart of Tecmo Bowl because it bring back memories of playing it daily after school. While other big name gaming chains are turning away from carrying older NES, Genesis, and N-64 games, we are blowing them out the door. I even mention to NES buyers that the Wii will be able to play them via the virtual console, and the responses I get are either "too expensive", "Wiis are unavailable", or "I want the original cart and controller, it's nostalgic."
Nintendo has really struck a nerve with both that generation of gamers, and the simplistic yet fun games it released. Perhaps when facing the high prices of next-gen gaming, the short suppliy of consoles and uncertainty of developer support of the PS3, backward is the only way to go for consumers.
To get you into the retrogaming mood, check out some classic NES soundtracks done in the rocked out style by either the Minibosses or the Kode.