I guess I'd built this book up in my mind as immensely dirty and graphic because I'd watched a few episodes of the TV show starring Billie Piper (you may remember her from Doctor Who) and as a result was slightly disappointed by the quantity of sexytime scenes in the book (That's right, I admit it).
The author is a London call girl who has a university degree and tries to hold down some soul destroying jobs but finds that she can make more money, in a way that she prefers, having sex for cashola.
She lets you in on some of the secrets of the industry and you'll be constantly entertained with stories about clients and her blunt approach to sex (which is frankly refreshing) but I found I was wanting a bit more when it ended.
So while I enjoyed the book I would suggest that, if you are left wanting, to look into her other works, including her blog. Brooke Magnanti came out in 2009 as the author of the book and now has several others. You can read her side of the story here. She's a fascinating woman with a healthy (though I believe some would disagree) view of her own sexuality.