I've been a BBP fan since the first edition in 2005. The second edition in 2007 was a significant update and refinement. The latest, 2011 edition, is not worth buying if you already have the second edition -- the information is essentially the same but the 2011 is printed on cheap paper and the contrast between text and background for most of the illustrations is lousy, e.g. black text on a dark grey background, white text on a light grey background. I found it very difficult to read. The online version (O'Reilly Safari Books OnLine) is slightly better because it allows you to magnify the low contrast images which makes them slightly more legible. Thankfully, access to the online version is included with the ink-on-paper book free via a scratch-off, lottery ticket-type insert at the back of the book. If I had to do it again, I'd skip the paper book from Amazon and just purchase electronic access via O'Reilly. This version is more legible and you can print important pages that you might want hard copies of to highlight, mark-up, etc.