I had a flight a couple of years ago (2010 or 2011) ATL-MSY where something similar happened. We had a short delay because of a late inbound a/c, then after boarding, that a/c had a mechanical issue that they tried to fix for about half an hour. They then deplaned all of us, asking us to stick around the gate b/c they had found us a new plane but had to bring it to the terminal...new gate was at the other end of B, then we boarded. The captain came on the PA and told everyone that the drinks were on DL that evening. All in we landed in MSY about two hours late.

I sent in a note to compliment the flight crew (and the GA) on their handling of the situation.