This not a history of the Byzantine Empire - rather it's a series of essays on different aspects of the Byzantine Empire with an overriding defensive attitude about the derogatory way the empire has been portrayed throughout history. The idea, apparently, is to try to present the important facets or characteristics of the empire in such a way that perhaps people who would not be interested in a straight history of the subject might be challenged to read about it, and change the attitude, which still prevails to a large extent, that there wasn't much to admire or even be interested in about the late Roman Empire which was ruled from Constantinople from the fourth to the fifteenth centuries. Basically, it's a highbrow Complete Idiot's Guide to the Byzantine Empire.
That having been said, I like the strategy and I like the book. By skipping the chronological history of the empire (which at 1100 years takes a while to tell and buries anything really interesting) it picks and chooses aspects of the history, telling you why the empire was important. Whether it was Hagia Sophia, or iconoclasm, or eunuchs, or the siege of 1453, the two dozen or so things that are important are highlighted and given a chance to breathe.
My favorite (largely I think because of the music) history of Byzantium is still John Romer's TV series from about 1998, but this book adds quite a bit to it by providing if less poetic, more persuasive analysis of many issues.
For example, I never really understood before what the driving force behind iconoclasm was - Romer makes it seem just another random bizarre theological dispute - something the Byzantines were always prone to. Its advocates' motives are never really explained, and it's presented largely as the sort of tyrannical invasion on freedom of worship that we can be expected to abhore. Herrin, however, explains that it arose when the empire was sustaining repeated military defeats, and since God obviously would not allow his chosen to be defeated, there had to be some reason behind it - something the Byzantines were doing that they were being punished by God for. The emperor eventually decided that it had to be divine displeasure with the common practice of venerating or "worshiping" idols, which did admittedly have strong roots in pagan practice. From their perspective, iconoclasm made perfect sense as an attempt to get back into God's good graces. Far from a tyrannical whim, it was, from their perspective a responsible, and even a courageous act.
All in all, a good book, and a good addition to my growing library on Byzantium.