It'd be nice if Delta was at least consistent on things like this. Had a flight in early November that was delayed for an hour, then boarded, sat for another hour, then cancelled due to mechanical failure. Then we all had to wait another 45 minutes for someone in Ops to actually mark the flight as cancelled so people could rebook. As far as I know, nothing was offered. Once the flight marked as cancelled, I used SMS to rebook the next morning, so I suppose it's possible they were offering something to people who stood in line.