I can tell you what my perception of a hipster is, although I start think that hipster qualities exist, and may not make someone a hipster.
Kramer from Seinfeld was something of a Hipster (Elaine calls him such at one point). Although he no longer "looks" it, his values are the key point.
They are the hippies of the present day, with a little more fashion awareness. Though there is a distinctive style, they wear it with a very "devil may care" attitude. The men will generally be scruffy and wear tight pants, or other bold fashions, probably purchased from a thrift store. For straight male or lesbian hipsters it's as if to say, "I refuse to wear the gender straight jacked society forces on us." To a gay male or straight woman hipster it's as if to say, "I don't have to look pretty or posh or have a perfect body or prada-wearing budget to fit in and feel accepted. You're more likely to find a hipster with wine, weed, and a vegan meal than hard liquor, coke, and a steak.
The hipster can hold a job and is one that can make money and pay rent, but is not primarily focused on money as success. They probably read, and enjoy "causes."
I would say that they are a educated, cultured and eccentric version of hillbilly rednecks.
The true hipster feels comfortable in their skin, but still enjoys expressing themselves with their outward appearance.