The cover of New Moon represents the blurring or blending of cultural boundaries and differences that I am talking about here. The plot does as well. At the start of New Moon, Bella Swan, a sensitive yet strong teenage girl, goes into shock when her true love, the vampire Edward Cullen, breaks off his relationship with her (for more on this relationship, see the first novel in the series, Twilight). Eventually, however, Bella recovers, and forms a relationship with Jacob, a tall and handsome Native American with a hidden identity of his own. Essentially an extended re-thinking of Romeo and Juliet, New Moon explores the nature of love and the question of whether or not it is ever possible to recover from the loss of one's truest soulmate.
I found this second novel in the Twilight series a bit tedious in the beginning, as the somewhat implausible break up occurs between Edward and Bella, but I have to admit I found the romance and tension in the relationship between Bella and Jacob very believable and suspenseful. The high action at the end of this novel also works very well--it is easy to see why the Twilight series is so popular with teen readers, especially young women.
Part of the allure of New Moon, though, is not just the way vampires, humans, and other supernatural creatures all interact and blend with one another in relatively harmless ways; in addition, readers enjoy this storytelling, I suspect, because of the danger that always lies just beneath the cultural blending and "forbidden" interaction. Readers know that Bella is just a footstep away from becoming a vampire herself; readers enjoy watching Edward and other characters battle their more base instincts. New Moon reminds that full cultural integration and boundary erasure is not easily achieved, and is always frought with danger within a society that is still very Puritan and conservative, at its core. This is a lesson that Barack Obama has been learning on the campaign trail in recent weeks, as various conservative commentators have begun to question the influence of the Rev. Jeremiah Wright on his thinking and leadership skills (basically, casting Wright as a vampire, and Obama as Bella). It's a lesson that Eliot Spitzer, too, has learned the hard way (see the video below).