emonPi/base update now includes updating emonhub to python3! 
The update process includes the installation of Python3 and dependencies as well as a call to apt-get update which can take a little time on slower connections.
The emonPiLCD script and service-runner are still ran with Python 2.7 which remains on the system.
Thanks @bwduncan and @borpin for all of your help with this!