i used to have short spiky hair, and then when I got to college i didn't feel like dishing out the dough for a haircut, so I grew it long (right now it's just above my jaw-line, and this after a year of growth! Come on!). A lot of people have said that they really like the look for me, however, when I go places, a lot of time i'm judged poorly because of it. I applied for an office-type summer job and was treated like i was homeless, i suspect because of my hair, and for that I purposely looked at more unconventional places to work. I'm now working at a farm stand down the street from me where most of the guys who work there have longer hair than me!
Especially in the airport, i get some dirty looks from people (mothers, businessmen mostly. The airport employees are always much more personable with me than them, though!) when I have my headphones around my neck or something. "dirty hooligan!" or something like that. Just don't let it get to you. You'll only have the chance to wear it long now, before you have to look respectable or whatever. My english teacher in highschool stopped cutting his hair in college and managed to get it down to his mid back, 2 years out of college, before the administration approached him to get a more "business appropriate" hairstyle.
I must say, it does present more challenges than a shorter haircut. my hair ALWAYS gets in my eyes. It's obnoxious. Especially when i'm driving with the windows down (which i usually do, I much prefer fresh air to AC), or when I'm eating or something, and it's not long enough to put it in a ponytail or something, so when i sweat, it's a mess. I'll probably cut it again this fall, get it short, grow it out again. I don't know how much longer I can stand it though. Maybe, i'll get a fohawk before going back to short and spiky.