I hope you like it and that it proves useful. You can download the PDF version here. It comes it at a respectable 32 pages. I tried to cover a number of topics with a focus on the fundamentals you'll need to get comfortably up and running.
I wrote it in markdown, the source is available on github. PanDoc was used to convert the book. The process was painless after a couple attempts. I'm also quite happy with the output (especially in comparison to how much work went into perfectly formatting Foundations of Programming using Word)
For the curious, the idea to write this hit me while I was going to sleep last Saturday. A little over half the book was written on Sunday, in around 4-5 hours. The MapReduce chapter was taken from a blog post I had already written (with necessary tweaks). Perry Neal provided some really quick turn arouns for initial edits/feedback. Of course, given the speed at which this was done, corrections and feedback are welcomed in any format (email, comment, pull requests).