1) Norah is prodigal daughter of her upper class family, hailing from a prominent and tightly-knit Armenian community. While her family didn't show off their wealth quite as extravagantly as their neighbors, hers was a white picket fence life with private schools, country club memberships, and a new car in the driveway every year. Norah's education was paid for, her wedding was paid for, and even her first home with her husband Chris was paid for in-part by her parents.
While everyone else in the book grew up on the poverty line in their respective ethnically-delineated neighborhoods, or managed to make it into the middle class after years of hardship, Norah was set for life. This is why she comes out of it so hardened when her life finally does fall apart. Money equates to falseness, and falseness is to be avoided at all costs. She doesn't miss having money, but she despise those who still do. Maybe this isn't so healthy, and maybe this lacks some self-reflection on her own privileges, but that's the world view she begins with at the start of the series.
2) Norah graduated with honors with a double major in English and creative writing. Since Hannah was born, all of that useful information has largely been replaced by the subtle nuances of My Little Pony canon and the full Pixar filmography. When dealing with children, this information comes in handy, but, to her chagrin, it's not usually a great way to lead off at a party. At least Adam, with his Irish horde of nieces, nephews, and preschool-age second cousins, understands this plight.
3) Don't ask Norah about Jem and The Holograms. You'll regret this. Drunk Norah won't let an opportunity to explain her feelings on Kimber and Stormer's relationship pass her by. Also: under her bed, there's a shoebox full of pictures of Young Norah in various Jem Halloween costumes. Drunk Norah will tell you all about this, as well.
4) Norah will be the first among the cast to have a child after her powers are activated. Already a single mother to a non-powered kid, the idea of having another, undoubtedly powerful child will be a serious and terrifying issue for her to grapple with later in the series. The nature of the father's powers will further complicate this for her, since there's no telling what abilities their children will end up having amid such a chaotic genetic mix.
5) While the powers of the rest of the cast are largely self-contained and self-regulating (Clara is fast, Adam is strong, Bridger sees the future, and Kyle can't be hurt), Norah's are constantly evolving. What began as the power to manipulate gravity has slowly developed into the ability to generate force fields, control electromagnetic radiation, and pass through solid objects by changing her own density. No one really understands why she has these powers. Kyle, Clara, Adam, and Bridger's abilities are natural extensions of their personalities, skill sets, or other factors, and it doesn't make a great deal of sense to see a school teacher tap into the base forces of the universe.
However, as she learns to control her powers over the course of seven books, this dark horse proves to play an important role in a much larger story.
6) Norah has encyclopedic knowledge of Coen Brothers movies. This is much better to lead off to parties with.