Early last year I was on a flight with a mechanical delay, missed a connection, and was more than three hours late. I complained at the LAX service counter and was given 1,500 miles (it sounded like they decided 500 miles/hour was the going rate).

Then on the Sunday after Thanksgiving I had a mechanical delay, missed a connection, and was several hours late. I got nothing but an apology letter from somebody in marketing the next week. I didn't try talking to anybody that time, though, since it was in SFO on a very busy day and there were a bunch of weather related delays - I was just happy to get on the next flight out as a standby. Had I been stranded there overnight I'd have been a lot more unhappy.

Given the convoluted routings some people take for extra miles (I do it too), 5000 miles for 2 hours of sitting is a great deal!

Edited to add: My mileage summary showed: "UAL SERVICE CHECK COMPENSATION BONUS 1,500 1,500" with the miles listed under the "Actual" column.