In one word: Refreshing.
Sat with it for two consecutive nights until my eyes started hurting. He describes his own academic journey - as a confused graduate student stumbling upon a completely unexplored subject - ecstatic at his finding but marvelling at how it remained unexplored for so long. But as he said, things had to happen in a particular order .
As for the science, it's presented in a completely accessible way - it's supposed to be for general reading. (Book Description covers it all).
He presents how properties of complex systems depend not only on interactions between individual components, but also the topology of the network on which these interactions occur. It seems obvious to us, and it did to him too, as to others before him. But despite such ideas prevailing long before Watts, Strogatz and Barabasi arrived on scene, there was little progress without sufficient computational tools available.
He continually stresses on understanding and appreciating the particular system under study, while sieving out irrelevant details. He also discusses universality classes, and the general applicability of so many results. His presentation leaves you with an impression of good science , done by good scientists, both of which are equally important and remarkable.
Given my own interest in the subject, it made the reading even more pleasurable. His enthusiasm is infectious, and his ending tribute to science left me with a warm, happy feeling about choosing this career.
I think the autobiographical style is what makes it such a delightful read. Easily recommended for everyone.