There are a number of errors in the metronome's page... Lindy Hop and the breakaway were not created by George Snowden, but he did name it. The breakaway was a step used in the dance Texas Tommy Swing from California, and when combined with the Charleston from South Carolina, and mixed with various jazz steps/dances the dance that would be known as the Lindy Hop was born... The name Jitterbug did not start as any kind of differentiation between ground bound and aerial swing dancing... it was just another name applied to the same dance.

And from what I have read the term Jitterbug applied to the people who danced and it was originally perjorative, i.e. dancing like someone going through delirium tremens. Over time it lost this conotation and now most people mean Single Time East coast swing when they say Jitterbug.

Check out this website for all the info you need:

http://www.streetswing.com/histmain/z3lindy.htm