I filed issue 10044 at the github site, but it has been open for a couple of weeks and the only activity has been a few other people confirming the same problem.
In hass 0.56.x and 0.57.x, using the official Docker image, the front end says that zha could not be set up, and this error is in the log:
2017-11-05 15:01:31 ERROR (MainThread) [homeassistant.setup] Error during setup of component zha
Traceback (most recent call last):
File "/usr/src/app/homeassistant/setup.py", line 191, in _async_setup_component
result = yield from component.async_setup(hass, processed_config)
File "/usr/src/app/homeassistant/components/zha/__init__.py", line 87, in async_setup
yield from ezsp_.connect(usb_path, baudrate)
TypeError: connect() takes 2 positional arguments but 3 were given
I have to roll back to 0.55.2 to get it to work again. @rcloran are you able to take a look?
I gather other people are able to use zha in the latest versions.