You should definately check out Howard Bloom's The Lucifer Principle because it deals very well with social structures, how a society behaves like an organism and evolves through the replication of memes.
Hi - Duncan J Watts excellent "Six Degrees" is well worth a read. This is a first person account by a scientist who has been at the forefront of network theory: and he writes with humility rather than self aggrandisement - explaining the subject clearly and demonstrating why its pretty complicated as a science even though the underlying ideas are quite simple. Enjoy!
Try "Linked: How Everything Is Connected to Everything Else and What It Means for Business, Science, and Everyday Life" by Albert-Laszlo Barabasi. Shows how the internet itself became a tipping point and now has a "mind" of its own.
"Fooled by Randomness" by Nassim Taleb, although its starting point is the stock market, is actually on the same underlying subject. It's a very good read, in the form of a rambling personal narrative, but it's still intellectual rather than "pop" culture. Really a terrific book.