Yeah, when I first got my PS3, I immediately noticed how much dust it had gathered on its surface during a single three-hour play through. I thought it was just a one time thing and forgot about it, but more and more dust began to accumulate on the surface as time went on... until I started to wipe it clean after every use. Since then, I've been keeping it covered with a small hand towel when not in use. I still wipe off the ports and vents every weekend too.

I do, however, live in a very dusty environment, and my entertainment center is right next an open window, so take that for whatever relevance you will.