As a Brooklynite myself I have many lady friends that have to deal with this on a regular basis in NYC. It's a real problem here (more so than other places i imagine). Everyday leaving the apartment is like walking into a battle ground for women in the city.
Those of you that are saying the guys in the video "are just being nice" are displaying a shocking lack of understanding in regards to subtext. While some are more aggressive to others, they are all in essence trying to get laid and are sexualizing the girl walking down the street.
Let's not play dumb here, we all know when it's appropriate to talk to someone. Perhaps there is some eye contact, maybe you are at a social setting that invites conversation, etc. With videos like this women are telling us men that they are not comfortable with this type of interaction. And you know what? We should all be able to respect that. No one is saying you can't say hi to someone. We're asking you to be aware of the situation
run away!