the inside word from GS is we don't pay enough for ArchiCAD in order that they afford a couple of graphic design students, to drastically improve the interface. unfortunately, the interface has gotten so old and out of touch with the competition, changing it now would be akin to taking away drafting boards and giving users a mouse and keyboard -- most of the userbase is so old school they wouldn't be able to work it out, not to mention the complaints phoneline to GS would be getting several calls a week!
it's hard now to imagine them pulling their finger out and updating, it might be easier to try a favorite Autodesk trick, ie. supercede it with something written by a smaller competitor.
sarcasm hat off
as suggested, Modo and Adobe CS5 are slicker than slick, easy on the eyes, they have clear, legible, icons and text, with resizeable, flexible toolbars and they function seamlessly and fluidly. none of which currently desribes ArchiCAD. I really hope they can find the time to look properly at the most used aspect of their program.