GalleyCat raises the issue of an author's age.
Is a teenage writer's voice more genuine than an older writer writing for the same YA market? Is it better to write in the midst of teen angst, or looking back on it from a few years distance? Can a teen only write for a teen market (which seems to be the subtext of the discussion)?
Does age matter? is it shorthand for life experience and craft learned?
And like most things in pop culture, different answers suit different people--readers and authors. Although I am reminded of poets such as John Keats (died at 25) who wrote brilliantly.