Well, the installation worked fine, but I'm still going back to Apple's X11.app. XDarwin intercepts cmd-W and cmd-Q to mean close-window and close-application, respectively (though if you hit cmd-Q, XDarwin will ask for confirmation if you have any open clients). These interfere with some fairly common keybindings (meta-W, meta-Q) in Emacs, which I use all the time.

I could, in theory, muck about with xmodmap and use option for meta instead of command. But my hands are too used to using command for meta, and I really don't want to deal with the frustration of killing my emacs buffer (repeatedly) when I really want to save the current region to the kill ring. (That's "copy" for those of you out there who don't use Emacs.)

The cmd-tab bug in Apple's X11 is annoying, but nowhere near as annoying to me as the interception of cmd. Oh, well; it was worth a try.