I'm in the process of reading two new books and will be posting reviews on them in a few days. The first is OpenX Ad Server: Beginner's Guide. A sample chapter is available online. We'll see if it lives up to it's name because despite my technical knowledge and Linux experience I've never used or even looked closely at the OpenX ad server.
I'll also be taking a look at Funambol Mobile Open Source. Here's another sample chapter. This one will be interesting because I already run a Funambol server and I have to admit that scraping together the necessary information to implement it without any printed material was a bit of a challenge.
Both books are recent publications from Packt Publishing. Packt specializes in books that cover beginner to seriously advanced computer systems management and development topics, and include quite a few that cover open-source software. My team here already used their RESTful PHP Web Services book when we were developing some backend solutions for the office, and found it to be a great primer on the topic.
