The good thing about the circumstances of his death is that we have a rough correlation between the brutality of the means with which the North African dictators suppressed revolutionary sentiment and the consequences they suffered. In Tunisia, Ben Ali gave up and fled. Now he can't return to Tunisia, but he's living in exile in Saudi Arabia. That's what we hope dictators do once popular sentiment for their overthrow rises, and for doing it he got off easy. In Egypt, Mubarak made a stronger attempt to hold onto power, but stepped down. Things turned out worse for him, as he's facing all sorts of corruption charges and has health problems, but I don't see that he'll meet any sort of violent end.
And then there's Gaddafi, whose bloody suppression of political dissent far outstripped the others. One of the things that made it easy to support NATO intervention in Libya is that the daily death tolls that resulted from war were much greater than the daily death tolls from Gaddafi's peace. Here's an article describing how Gaddafi massacred 84 civilians one day and 140 the next. He was sending helicopter gunships and artillery to kill peaceful demonstrators. As far as I know, the other two didn't use that kind of heavy military force against their own citizens. In contrast, the daily death tolls from the fighting in places like Misrata were usually in the single digits. The worst I recall seeing from the fighting after NATO got involved was a death toll of 25 one day.
The rather graphic message to dictators from Gaddafi's end is to get out while the getting is good. You want to end up like Ben Ali, and not like Gaddafi.