I picked this book up the last time I was in Rome in 2011 and have only now systematically read through it. It is a detailed guide to the main Roman sites in Rome itself and is very detailed. It gives an excellent background to the major monuments and archaeological zones accessible to the public from the Forum Romanum to the Nero's Domus Aurea. It gives an excellent picture of these archaeological remains.
The language is rather technical, so some background in archaeology and Roman history is helpful. I found particularly interesting the discussion of the state of the ruins in the mediaeval and Renaissance periods as well as the various attempts at preservation from the eighteenth century onwards. It is a little dated, given the re-opening of the Domus Aurea and some other finds around the Colosseum. Still an excellent guide and well worth going through if you're an archaeology geek on the way to Rome.
Very informative. The prose is perhaps a bit dry. If you can handle carrying it around, it serves as an excellent guide book for visiting the monuments of Rome.