>> Can you control, say, Apple Mail or Safari with XMonad?
> Ah, you're in the X11 uber alles camp.
:-)
Not at all. But I am in 'the why run two completely different window
managers simultaneously, when it's far more comfortable to be running
just the one' camp. But the ease with which your suggestion rolls off
I have uses for X11-based stuff (have not, for example, found a single GUI IRC client for native Aqua that is really usable; also, I regularly do support for Unix/Linux stuff so need that UI available) and the X11 and Aqua stuff differs significantly enough that I don't have issues switching between them. Except that it's far easier when they're on the same machine than when one is confined to a Linux VM, which in turn is easier than when one is confined to its own hardware.
Maybe if the X11 world offered a user interface that didn't feel like it was written by bonobos on LSD, I'd use it full time. I'd even be willing to put up with driver hell if the UI weren't just so horrid. I mean, I'm not fond of Apple Mail but it's way more usable than Linux offerings.... But in the meantime, I need it to be around and I want it to be conveniently available, without being in my way. XQuartz serves the purpose.