I have just started reading "It's Complicated" by Danah Boyd. You can download a copy of the book as a pdf from her website. Its about teen use of social media.
But so far I have reached page 7 of the introduction and I am already grinding my teeth
"Social network sites downplayed the importance of interests and made friendship the organizing tenant of the genre"
No, a tenant is someone who occupies a rented property. Danah meant tenet "A principle or belief"
On the same page
"Rather than being seen as a subcultural practice, participating in social media became normative"
I think she probably means "normal" - rather than "Of, relating to, or prescribing a norm or standard" After who exactly might be imposing this standard? Or is she talking about peer pressure?
Once an author has made one error of this kind - which we all do, I admit - it becomes hard not to look for more.