I like the style

it's rather dark, but then again so is being a teen

however I do think that cuts your target demographic in half, just my opinion of course...keep in mind i'm 24 now
You've got (at least here in the states) a few different categories of teens. and while the dark (read: goth) mentality is a pervading theme these days (read: pop culture-esque)...u're leaving out bubble-gum pop, Abercrombie (that's a name brand pop), etc. So one suggestion would be multiple styles for your users to select (much like vB.org offers)
see if you can swap links with other like-minded sites...that will do a ton to boost google rankings, spiders love reciprocal linking!