In a sentence, GG clips to your belt and, when you touch a club to it before hitting a shot, tracks your shots for automatic and easy compilation of statistics showing you where you hit your ball and how far with various clubs, and other assorted stats.
I've charged two of the systems already, and a third will be charged later, so we'll all get our first rounds in with them tomorrow. Much more to come.
P.S. The packaging is great. I really appreciate solid, well designed packaging.
If anyone has any questions, please feel free to ask them here.