Book: BackTrack 4: Assuring Security by Penetration Testing

I won't write such topics frequently :-) but an interesting book have been released recently at PacketPub:

BackTrack 4: Assuring Security by Penetration Testing

Based on the table of contents it goes through many of the tools found in Backtrack, and there is a chapter about the pentesting methodology. There aren't so many other books like this in my opinion.

You can order it here, and the 2nd chapter is available for free:
http://www.packtpub.com/backtrack-4-assuring-security-penetration-testing/book

It can be downloaded either in PDF or ePUB.