I think I've got bad luck then! From what I can tell, ours was built in the 50s or 60s. We can hear the neighbors going up and down the stairs, the vacuuming, when they play music, when the baby cries, when they open or close doors, when they're talking in the kitchen, and when the toilet flushes.
None of this really bothers me, so much, they're great neighbors, but it's there, and I've heard less in flats that I've lived in (that were newer, granted). Some of the other people we've had next door were just terrible, though. One guy was a heavy smoker and he would just be up all night hacking up a lung in addition to his frequent arguments with various people and his affinity for loud techno.