There has to be something with Narcissa...
I've once heard the (kinda strange) theory that she might in some way be related to Lily Potter, for Lily and Petunia were both named after flowers, and Narcissa is a flower name as well...so she might be a long lost Evans sister...(hasn't JKR confirmed that we're going to find out about a dark secret of Lily Potter?)
Very good theory, it sounds interesting.
Yeah Narcissa will be part of the next books, we will have to learn something about her, and surely will play at least an small role in the next three books.
Just one more question about Narcissa...what do you think what kind of character she is? A true Malfoy, which means kinda evil by nature, maybe a supporter of Voldie herself, or a rather goodhearted woman corrupted by Lucius?
No way she is good. If she marries omeone like Lucius they should be very similar (and if not Draco wouldn't be that evil, he would have some part of his mom, no?)