Eversince the gothic emerged from and contrary to the Romance tradition, it tried to (in its classical era) stand up to some of its central characteristics: bohemian art, imagery, setting, etc. This opposition emerged as the dark, sharpened, grotesque...gothic features of art. It was only a matter of time before these aspects mirrored into real life epitomes: people wearing black as much as possible ( a symbol of their rebellion against the romanced aspects and perspective upon life ), leather and lace (a metaphor of the decadence opposed to the romantic impositions upon society), spikes and pierces (a symbol of pain as inherent to human life, weather we like/accept it or not).
Into music, it translated as rebellion, decadence, the same inner impulses to revolt, adapted to each person`s individuality). Consequently and taking into consideration the constant evolving of music and trends, bands such as Haggart (metal with symphonic influences ), Nightwish (appealing to a larger variety of goth listeners).
All in all goth will not disappear as long as, on the one side, the desire to oppose the romantic and dreary and on the other the inherent need to express one`s dark inner demons will persist in the individual`s manner of expressing himself.
http://1.bp.blogspot.com/_-jo2ZCYhKaY/TAcu2GGvO4I/AAAAAAAAIEA/DLX6QrTmkXY/s1600/horrifique+%28gothicwallz.blogspot.com%29.jpg

I think that this Style will always be around in one form or another..

There music and there style has strong dedicated following though the bands of today in this genre have changed a bit from the older stuff i grew-up with like missionary and Dead Can Dance..

I Personally enjoy the look of goth and there more orchestrated Music.

The term "goth" is very blunt, so no it will never go out of style. It can be death rock, industrial, metal, or electronic orchestral music. I think the reason it has stayed popular for so long is because "cult" bands or less mainstream artists tend to be a little more timeless, Bauhaus is my favorite goth band and from looking at these girls I'm guessing their fans as well. Even though Peter Murphy is old enough to be all three of our fathers. Its always promoted being an outcast and simply being obscene, where as metal and punk tends to be a little more direct as far as promoting certain politics or religious views.

I hope it doesn't, I'll have no bands to go see live if it does.

Here's a contrast to show how wide the term is, both songs are "goth"

Bauhaus:
http://www.youtube.com/watch?v=l4rqbs0vxK0&feature=related

Killing Joke:
http://www.youtube.com/watch?v=MzG_S-GwAIo