I am struck, in this reading, by how very subtle JA is in conveying to the reader that Miss Bingley entertains at least some hope of becoming Mrs. Darcy. She never says so much - the closest she comes is in Chapter 10 after Darcy asks Elizabeth about dancing: 'Miss Bingley saw, or suspected enough to be jealous...'

Everything else we are led to very gently by
1)the subtle change in her manner to Elizabeth - at first she is simply a coarse country girl like the rest, but as Darcy begins to like her Caroline becomes much more cutting
2)her constant attempts to engage Darcy in conversation

So my curiousity is now engaged...does she have any true affection for Darcy at all? Or is she fond only of Pemberley and the ten thousand a year? Does she have any knowledge of Darcy's character at all? Or does her feeling start and end with "hey, my brother's best friend is handsome and rich, this could be good....?"