GVR said to expect a five year migration. We are four years in. Major projects like NumPy have had support for a while. Pyramid supports it. Django has good enough support that library authors can start migrating their changes. Python 3.3 took out a major source of 2/3 conflict by putting u"" strings back. It would not surprise me to see a lot of newly updated code be 2.7/3.3 or greater as a result, but it will hasten the conversions.

All in all, with a year left in the migration path, I'd say we are doing OK. The VM is in good shape for production use and the libraries are coming along well.

I think the biggest danger is all the hand-wringing about how everything has gone wrong, who didn't read the fine-print to start.