Well, not a bad start, two days in a row is pretty exceptional for my level of blogging over the past coupla months...
Theissen does a great job of writing a book about Jesus, without actually having Jesus in it. All the stories are told from the periphery of events in Jesus life, and the result is an intriguing and thought provoking book.
Theissen himself is a Biblical scholar and theologian, so has a very broad understanding of the 'source material' and context of the Gospel stories.
I should also say, it's entertaining and a good read.