Publishers Weekly says, “Young adult literature is hot. According to the Young Adult Library Services Association, sales of books aimed at the 12–18 age group grew 20% between 1999 and 2005. With general market YA such a hot commodity, and religion soldiering on as a steady growth category—up 5.2% in 2007, according to the Association of American Publishers—it's no surprise that Christian publishers are scrambling to marry the two success stories. A number of Christian houses have started their own YA lines, aiming to be relevant to teens' needs while remaining true to a core Christian message.”
Read more here, including quotes from someone I’m working with on my series with Lis Wiehl, Allen Arnold.