I have a pretty vast personal list of reasons why I do not, and shall not ever, have a facebook account.
Other than the most blatantly obvious and mundane reasons to have a facebook account - I would like to seriously hear why one should have one. The obvious being "I keep in touch with my friends" -- well, I keep in touch with my friends - most of whom have an account. Our relationships have never suffered from my not having an account.
I find the more insidious motives behind facebook and its founder to be hands down a showstopper from my perspective.
So, other than the ambiguous "keeping in touch/sharing photos" with friends, what would be a compelling reason to have an account.
The "everybody else has one" is rather flimsy.