Getting mine cut to my collarbone next month so I'll go with short :D
Yes they definitely prefer long hair, past the shoulders. I've heard many men at work and such talk about how ugly it is when women cut their hair off, and they even spoke about this one particular woman, she's fairly young, can't be more than mid 30s (and these guys were in their 40s and up), and that she used to be very attractive until she cut all her hair off. I mean, I think she has a pretty face but now she has hair shorter than her chin and it does not look very feminine and pretty on her.
I feel like short haircuts are a "girl pretty" thing, girls may like a bob but men will not be as sexually attracted to it.
Not trying to be mean, sorry, I'm just telling you what I've seen. I even think most girls look prettier and more feminine with long hair. But it's your call.