I'm a guy with long hair. I first grew it out in high school as I hit my rage against the machine/down with the man phase. I was one of the geeky uncool nerdy guys at my school so growing it out just made me a geek with long hair. But the next year I tranferred to a new school and within a month I had my first girlfriend ever. The hair was what made her notice me but then again I also had an attitude change from wallflower to more outgoing and confident, it was a big "starting over" time for me.
Long hair doesn't automatically make you a chick magnet but if you can pull it off it can help. Every girlfriend I've ever had including my wife was first attracted by the hair, and girls who are put off by it probably aren't my type anyway.
Even with the ring on I've had chicks I've known for like 5 minutes, meeting at a party or whatever, ask to play with my hair. Its great. And if I cut it off my wife would kill me, not that I would, there's nothing quite like just sitting and having a woman play with your hair.
What's funny is people automatically assume I'm a hippy - and I'm a salary 8-5 M-F suburbanite, I usually vote Republican and I've only smoked pot once in my entire life.