I'm programming desktop applications in Racket, but unfortunately for many purposes it is, as of now, too slow. Especially application startup time is painful, and text% and other essential components of the GUI are way too sluggish for professional end-consumer applications. Maybe the Chez-based rewrite will help, but I'm not betting on it. Parts of the GUI library are just too complicated, and sometimes for no good reason (for example, style lists or the way it deals with snips internally).

I'm probably ending up with prototyping in Racket and writing the final application in Qt or Lazarus.