Is there any GUI for R that makes it easier for a beginner to start learning and programming in that language?
You can also try the brand-new RStudio.  Reasonably full-featured IDE with easy set-up.  I played with it yesterday and it seems nice.

Update

I now like RStudio even more.  They actively implement feature requests, and it shows in the little things getting better and better.  It also includes Git support (including remote syncing so Github integration is seamless).

A bunch of big names just joined so hopefully things will continue getting even better.

Update again

And indeed things have only gotten better, in rapid fashion.  Package build-check cycles are now point-and-click, and the little stuff continues to improve as well. It now comes with an integrated debugging environment, too.
