Username or EmailPassword
Or it will be as useless on OS X as on Windows. I'm sure most of GTK+ features can be implemented using native OS X and Windows controls and dialogs, so that GTK+ would in effect become some kind of binding to MFC (or whatever Windows uses now?) and Cocoa. That way it wouldn't look foreign and would redraw with the normal rate for native controls. So far, looking at Gimp screenshots in OS X, I can see that GTK+ does drawing itself, even if without X Window. That's not a proper way to do it.