I have followed Ben Powers' advice to change the interface aspect from a somewhat austere X11 look to a nicer Aqua look (see http://article.gmane.org/gmane.comp.graphics.inkscape.user/3967)
I'd like this. I usually use Inkscape on my Linux computer, but I'm trying to get my wife to use it more, on the Mac. Having the nicer looking theme on the Gimp helped her make the transition more easily.
I've never actually been successfully building GTK on OSX, and don't have developer tools on her machine, so I don't know that I can actually help on this, but I would definitely cheer for it. :-)
Thanks, -- Michael Moore ------------------------------- www.stuporglue.com -- Articles, software and computer tutorials. www.stuporglue.org -- Donate your used computer to a student that needs it.