Egan has been my favorite author for years. I like his earlier works (like this one) much more than his last books. I have the impression most books he wrote and published in the last 15 years require a Ph.D. in either Mathematics or Theoretical Physics. Permutation City was my absolute gateway drug to his work and I could not stop talking about it when it first came out.
A series that explores similar ideas (although to a much smaller degree) of uploading, artificial life, and transfumanism, I've been enjoying lately is Pantheon. I just wanted to mention it here since I think you guys will enjoy it.
Zendegi is a recent book that is quite readable - but I agree regarding most of the others. Permutation City is one of my favorites but I think Diaspora must be my very favorite.
I read The Book of All Skies and quite liked it, but yeah, I basically just skimmed over the especially mathy sections. In that one the math is about (spoiler?) how gravity would work with a very unique planet, with comparisons drawn to electrostatics, I think. It was still enjoyable because it's still unique and interesting sci-fi.
A series that explores similar ideas (although to a much smaller degree) of uploading, artificial life, and transfumanism, I've been enjoying lately is Pantheon. I just wanted to mention it here since I think you guys will enjoy it.