To anybody looking for a PDF version: I've written a script that converts the Markdown version on github into a PDF via LaTeX: http://github.com/duairc/progit/master/latex

I don't have the PDF on Github because it's so big, but you can get it here: http://netsoc.tcd.ie/~duairc/progit.en.pdf

Its output is mostly fine, but there are a couple of very long lines in verbatim environments that go off the margin. I'm working on a fix for this, but it's not too serious a problem really.