As this is one of the more debated side issues of ST XI, I thought I'd offer a quote from Nichelle Nichols, the original Uhura, on the subject:

"In later years, especially as the women's movement took hold in the seventies, people began to ask me about my costume. Some thought it was 'demeaning' for a woman in the command crew to be dressed so sexily. It always surprised me because I never saw it that way. After all, the show was created in the age of the miniskirt, and the crew women's uniforms were very comfortable. Contrary to what many may think today, no one really saw it as demeaning back then. In fact, the miniskirt was a symbol of sexual liberation. More to the point, though, in the twenty-third century, you are respected for your abilities regardless of what you do or do not wear. I'll tell you one thing: I would not have worn those silly high-water bell-bottoms with the ruffle on the calf the guys had to wear for anything."

(From her autobiography, Beyond Uhura. Personally, as someone who has worn a miniskirt now and then and felt comfortable in it as well, I'm with her.)

*icon courtesy of other famous miniskirt wearer in sci fi*