Hi FredB,
I've just tried it out and for me it works.
Which GetBundles version do you're running? It's the first line in the Log Drawer. Mine is: 11/22/2010 23:51:10 TextMate[GetBundles] GetBundles – version 1.3 – .....
If you do not see this version string then you should update GetBundles.
On the other hand I encountered that GitHub has sporadic "problems" or hangs. But to be honest I've never seen that message.
Cheers, --Hans