I lived in Bucuresti for about six months (not in a nice part of the city either), and while I heard the stories about the dogs, they were never a problem. You do see them running around from time to time, but I never saw or heard of anyone being attacked by them. The largest bunch of them that I can remember hung out near the metro station close to Carrefour and I would pass them with my groceries and they still didn't come after me.