I voted for nano+uCode (my own IDE, which is still pre-alpha).
uCode is designed for microcontroller and SPLD/CPLD use.nano, because it's the only editor on a Mac, I can be sure of handling Unicode well. (TextEdit messes up unicode files, Xcode 2.5 seems to work with Unicode, but Xcode 3.x messes it up).
I do use Xcode 2.5 frequently, but D is not integrated.
