There's also (probably, I didn't count myself) a record number of Python implementations that are not CPython (including Cython, Pythran and similar projects) as well as CPython forks (Pyjion, Pyston, the project announced by Guido, etc.)

Also: judging from https://github.com/python/cpython/graphs/contributors, the "all time low number of contributors to CPython" assertion doesn't seem to hold. In terms of committers, and according to this page, I count a similar number or slightly higher of committers (50+) over the last year, similar to over previous years (including those that seem more active in terms of commit counts on the graph, like around 2010).

  S.