Support for Python 3 has sort of teetered on the edge of prioritization for a while now, but this article from the Python Software Foundation regarding the future of support for TLS 1.0 and 1.1 should give us a reason to consider a stronger position. Essentially, the stock distribution of Python that comes bundled with OS X and now macOS does not support TLSv1.2, soon to be required by Fastly, the CDN provider for PyPi where our binaries are hosted. In other words, pip install nupic won’t work.
June 2018 is a long ways off and there’s plenty of time for the situation to change, but given that this is a security-related issue, I think we should err on supporting the new thing rather than holding on to the past. To that end, I’d like to propose higher prioritization for python 3 support in nupic.core and nupic. Doing so now, rather than later, will give us plenty of time to work out the kinks.