It's probably at least a few years away, which can be a lifetime in teen casting. A couple years ago I made this (http://img465.imageshack.us/my.php?image=liverunbig5xc.gif) for fun, for my choices, and it's already probably pretty out of date (though some of them might still be doable).

I can't think of any young actors/actresses who've jumped out at me recently who might work, but I'm sure they could be found.