I would also love to be able to do this. Any help sorting out how to do this through the GUI toolkits would be great!

I'd very much like this as well!

Is this not closed by #8394 (i.e. mpl2.1)? (see also #4746 (comment))
Feel free to request a reopen if I missed something...

I still get

$ xprop | grep "WM_CLASS(STRING)"
WM_CLASS(STRING) = " ", " "

when running

In [1]: import matplotlib.pyplot as plt

In [2]: %matplotlib
Using matplotlib backend: Qt5Agg

In [3]: plt.plot()
Out[3]: []

In [4]: 

with matplotlib installed from conda-forge

conda list matplotlib
# packages in environment at foo/mc/envs/dp_dev:
#
matplotlib                2.1.1                    py35_0    conda-forge
ipython                   6.2.1                    py35_0    conda-forge
ipython_genutils          0.2.0                    py35_0    conda-forge

Well, that's because in your case IPython is setting up the QApplication, not matplotlib. Can you try without IPython?
matplotlib could use setApplicationName to update the QApp's WM_CLASS, but I think it should not (because in general, matplotlib could just be embedded in some other application that does not want WM_CLASS to be fiddled with).
So I'd say the issue (if any) should be reported to IPython.

Without IPython it does work. Would it be possible to have this be settable somewhere?

It's just a matter of calling QApplication.instance().setApplicationName(...). Again I think this should be IPython's job, because they own the QApp.

@CJ-Wright you can also do that call and set it to what ever you want (such as xpdacq ;) )

attn @Carreau can we do this on the IPython side?

@tacaswell The hope was to use Awesome both at xpd and on my local to place the various windows where they needed to go at instantiation time. What is the best way to access the QApplication and such for an individual plot?

We (IPython) create the QApplication at a point where we don't know that it's for matplotlib, so we can't set the application name to be matplotlib at that point. But if you can find the right place to put it in our code, a PR would be welcome.

@CJ-Wright The QApplication is a process singleton, QApplication.instance() will either return the singleton or None.

Please do not install Awesome on the beamline. If you are going to fill a screen with a fixed set of plots you are probably better off building a Qt Application with embeds all of your plots. That way you only have to maximize it reliably.

Closing, as "not a matplotlib issue" (IMO) per the discussion above.