Literary credibility of twilight?

I love Twilight but it is very easy reading, Its like a pg/ vampires for dummies Anne Rice novel. It's big enough to make you feel like you've accomplished something and it's very hard to get lost. The cliches are explained in the novel as though some of the typical characteristics of vampires are just old wives tales. I'm just happy that teenagers are reading, if the it wasn't twilight these girls were talking about it'd be something else...