still looking for a really great dev environment for MacOSX

After all these years with Hypercard, I am still looking for a really great development environment. Should run on MacOSX. It would be nice, if cross platform (PalmOS, Symbian...). Revolution seems to be quite interesting, but far from perfect. Eventually I will try to get SK8 running under MacOSX. Maybe use SK8 as a basis for a future Hypercard...