mpl master, python 3.5 from Anaconda on OSX Mavericks:

With the qt4agg backend, when I execute python subplots.py or pythonw subplots.py on the command line, only one of the three axes has anything drawn in it, and which one gets the line is random from one execution to another (although I never saw the upper right one get it). Furthermore, resizing the window does not correctly redraw the figure.

However, the shiny new implementation of macosx with Agg works perfectly provided it is invoked with pythonw.

I can't test tkagg because I can't get that backend to work at all with Anaconda.