From th OED online:
ADDITIONS SERIES 1993

Goth, n.

Sense 3 in Dict. becomes 4. Add: 3. Often with lower-case initial. a. A style of rock music, and the youth culture associated with this, deriving originally from punk, and characterized by the dramatically stark appearance of its performers and followers, reminiscent of the protagonists of (esp. cinematic) gothic fantasy, and by mystical or apocalyptic lyrics. Cf. *GOTHIC a. 3 e.

I would take exception with it still being characterized as a "youth" culture, because I still consider myself a goth at 31. I would add that the term "goth" was originally an insult to say that those branded with the label were "lacking in taste" but got adopted as a badge of honor early on. As far as the taste thing goes, I defy anyone to look at a goth and a rap fanboy side by side (as a comparison of those who follow a style) and tell me that the goth is the one without taste- the goth will be dressed in all black, generally in well fitting clothes, while the rap fanboy will be in baggy pants hanging somewhere between the knees and waist, gaudy "bling" jewelry, and various accoutrements sported by the latest rap star. The goth will be very polite, e.g. hold doors for ladies and say yes sir/ma'am, while the rap fanboy will be spouting rap lyrics, calling women something that I won't repeat here, and will generally be very menacing. (This does not necessarily mean all of either culture will follow this, but it is the most likely scenario)

We goths may be dark, but I'd say it's the rap fanboy who is evil.