I haven't read Permutation city or any of his old work precisely because I have been told his older work is not as good as his new, so I believe it's probably not representative. I have found his (newer) books to be very meaningful. The downside is that a lot of them require a certain mathematical maturity to fully appreciate, so I can't recommend a lot of his books to my "non-STEM" friends.

But considering you're a physicist, and you like SF... I thought it would be a good match! ;)

Sorry for the late reply. I'm getting used to dreamwidth, it's a lovely platform.