I've heard conflicting things about this from women and the internet. Some girls I've talked to say that they don't like comments about their appearance from strangers like "you're really pretty" but others say they have no problem with it, even outside a club/pub setting.
I told a nurse in a hospital a few months ago who was taking care of me at my discharge that I thought she was attractive. She seemed to chuckle/smile when I said that. My mother thought that was a bit inappropriate as she has a few colleauges in her office that say they've been creeped out by random men commenting on their appearance.
Would that be the attitude of most women in regards to comments on how they look or would they be flattered by it?