Since the phenomenon is <20 y.o. the usage you're after is likely also younger and thus not within AH's purview. But someone might be able to elucidate the origin of the term in the 1940s, 50s, and 60s which might allude to modern usage.

EDIT: So, according to the Oxford English Dictionary, "hipster" first appears in print in Jack Smiley's 1941 Hash House Lingo. This was a sort of dictionary of its own, cataloguing the specialized slang of American soda jerks and "hash-slingers" of the early 20th century. Smiley defines hipster here as "a know-it-all."

The next usage catalogued in the OED comes from Mezz Mezzrow's memoir Really the Blues, in which he defines a hipster as "a man who's in the know, grasps everything, is alert." Elsewhere in the work, Mezzrow links the hipster more directly to language: "The hipster stays conscious of the fraud of language. Where many ofays will hold forth pompously, like they had The Word, the negro mimics them sarcastically. As a final subtle touch, his language is also a parody, a satire on the conventional ofay's gift of gab and gibberish."

Most famously, perhaps, the hipster is codified by Norman Mailer in an infamous 1957 essay entitled "The White Negro: Superficial Reflections on the Hipster" which can be read in its entirety here. Mailer describes a subculture of urban white Americans who adopt the trappings of the black culture of the 1940s and 50s, which influences the Beat Movement and associated counter-cultural trends in the 50s and 60s.

I'm guessing at this point, but I feel as though Mailer's usage is closer to our current usage (although without the racial overtones) since we're describing a culture of young, often urban Americans adopting the trappings of another culture.