They do a good job of explaining the way Age Of Innocence works, but here's some more food for thought: just like in this show, May (Serena) is totally faking everything, pretending to be stupid because it's easier and pulling off majorly manipulative bullshit only when necessary. The empty anima blank slate she's perfected pretending (contrast with Daisy from Gatsby, also mentioned here, for another primer on how very, very far this sort of thing can get you: she explains it outright, hoping that her daughter will learn to be just as stupid as she's forced herself to be) is so attractive, in fact, that Newland (and this is just so Dan) spends a whole lot of time actually worrying that he's somehow going to damage her "innocence." So the whole story is actually a great big satire, in one way, on how fake the innocence in its Age actually is: May knows what's going on more than anybody else -- just like Serena -- and pretends not to care, because it gives her power.
Newland/Dan has these protofeminist sort of pandering ideas about "freeing" her that are really about his own freedom, and when the book has finally just completely broken him, he realizes that Serena's the freest of us all, because everybody else runs around constantly kissing her ass and making sure nothing disturbs her sanctity or sanity. She's transformed herself into a sort of goddess. In fact, the class stuff in the book is pretty close to this show, as is the emphasis on the meaning of clothing, décor, all that, and one of the coolest things is the way the van der Woodsen and Archibald types in the book are constantly being referred to as these ageless sort of inhuman monstrous angels. They are so far removed from reality that they don't have to take part in it: just look pretty. I mean, that's the book.
And then just like in this show, it matters less in Wharton's NYC what things actually are, and more how we've agreed to treat them: the only reason Ellen (Blair, on this level) isn't stoned to death on live television is because there are people with influence who adore her, and simply by saying she's okay -- Serena's role in her life -- make her okay. Ellen is on one level a complete maniac who rightfully terrifies and horrifies everybody... But on another level, the most human and complex and loveable character of all. It's only the reputation she gets from May's family and her other friends that allows anybody to even consider the fact that her outré behavior might be acceptable.