I have found this extremely useful - used it to write many things - from a set of scripts that bootstrap chef server onto a node from scratch to a file chunking program that optimizes log files to align with hadoop block sizes using multiprocessing and this. It made a lot of things very easy.
This version introduces many positive changes: specially 'Iterating over output' that I have been waiting for a long time.
Andrew wants to increase his support for MacOS and would like to have test results from "python setup.py test" (to run the whole test suite). One identified bug is: http://bugs.python.org/issue15898
I would love to see more people use this to simplify their work!
If anyone is interested in looking into the scripts I wrote to see what's possible, let me know.