Sorry in advance for the wall of china length of this post:
in high school, we had to wear a uniform. There were strict rules on accessories, makeup, nail polish, etc. But the point isn't to make you all look the same, and I can tell you that everyone looks very different in the same uniform. If you look at the 'caught in the same outfit' thread, you can see that people look very different even in the same clothing.
I haven't heard one girl from my school say she didn't miss our uniform (sailor blouse, tie, box skirt, knee high socks, cardigan, pullover, knit vest or blazer, loafers). It was a cute uniform, featured in a magazine once.. I can't blame those who hate it if their uniform really is hideous.
I'd say that our uniform said more about someone's interests than just regular clothing. It's easy to dismiss someone as a 'scenester' or 'diva' just by their clothing choice and stereotype their personality. With our uniforms you could wear house pins and club pins on your tie, even ones for academic achievement which said a lot more about someone than what 'clique' they belonged to. In our neighbouring boys school they had different ties for each club, which happens to also train them to dress for the occasion. Because of your uniform, people are forced to look beyond your dress and at you as a person instead.
It definately creates a sense of community and school pride. I'm not sure how to explain this, but it may be because of the common experience. Though I'm a long time grad of my school, when I happen to pass by a girl on the street wearing my school uniform, I get warm feelings. I feel like she is like my little sister.
However, it doesn't prevent cliques. The plus side to this is that the cliques are not based on your dress, etc but interests and for some reason academic standing.
I think those who oppose a uniform take it too seriously. Its not like you have to wear it everywhere, just in school or work (wherever its required), and it teaches you that appearance isn't everything. You can wear your personal clothes in your personal time, and studies have shown that people perform better in a uniform environment. When we had grub days, students really did tend lose their focus!
But if you really do care about appearance, don't forget how hot girls and guys look in uniform. ladies.. prince william in his uniform.. or your local firefighter hottie.
Can you deny how dashing men in uniform are?