I noticed that the release version Windows installer does not check for an appropriate version of pyqt but nonetheless builds the qtconsole stuff in the scripts directory. To avoid confusion, it might be better to explicitly check for this dependency, or at least not build the qtconsole material in the scripts directory lacking this dependency because failing to have the correct pyqt version is not apparent from running the corresponding executables.
Just a suggestion.
That does make sense, but it would mean that people who install IPython before Qt would have a different environment from people who install Qt before IPython. I think that might cause more confusion rather than less.
I believe it is standard practice to not change install behavior based on runtime dependencies (as opposed to build dependencies), since install order is not relevant.
I think better error messages (console messages don't count since ipython-qtconsole is a gui-script, and not connected to any terminal) should be an adequate solution.
I agree with @minrk. It would also mean that if they install IPython, then learn about the Qt console and add Qt, they'd have to re-run the installer in order to get working shortcuts. We can definitely improve our docs and error messages to point users in the right direction, but won't change the install-time behavior based on dependencies.
We make it pretty clear that we have a number of optional capabilities that require more than the stdlib, so I think this will stay as-is. Thanks for the feedback, though!