reduction in Unrest time and Population

With the new patch there us reduction in Unrest time and Population loss with tourism. Is it also a reduction in buildings sacking ?

No apparent change in sacking of buildings. And the reduction in unrest time and population loss is only helpful if you have the happiness to support it. I often find myself razing the city for a while to get the population down.

(My former favorite happiness-management gambit of letting the AI recapture the city, thereby cutting the city's population in half again, and then reconquering (and cutting pop in half yet again) and re-puppeting, is much less attractive in light of the new per-city warmonger penalty mechanic.)