we have a simple setup, and use python3.3.3. (Should be at 3.3.5 soonish) We have a dependency on pyodbc and they don't have a version for python 3.4. Also, we use pywin32. (Yes, on windows. We use it to monitor machines, do graphviz diagrams, xml-rpc, that sort of things. On windows mmsql environemnt. Yes i keep on top of it.
We try to do everything we need with the standard library, which is surprisingly good. Also, I do have one service using 2.7 because web.py. (Thank You Aaron!)