I've just released the latest version of coverage.py: coverage.py v3.7.1. The only changes are performance improvements in the HTML report, and a little restructuring to make Debian packaging a little easier.
The next version will be 4.0, and I'm looking for feedback about major changes you'd like to see. Coverage.py has never had an API-centric mindset, for example. Breaking backward compatibility will be OK if there's a good reason, and I'm dropping support for older Pythons, so it should be easier to make changes.
Send me your ideas.