Earlier quoted context omitted.
I think it depends on your habits. Facebook is unreliable for social interaction on a deep level for me because there is a negative cycle of reinforcement based on poor data. My closest friends are the ones who I want to hear the most about, and yet for some reason, their updates are the ones I see the least. Part of the reason was because my feed was flooded by people who used Facebook voraciously, though I consider…
Email is the least secure technology you can pick. For my communications, sharing birthday-pictures and so on, Id like to know that it takes more than to just sniff the somewhere along its path.
Similarly, if you post it on Facebook, people with access to Facebook's databases can see it. The risk seems to be pretty comparable to me, it's just different companies you trust. Certainly sniffing your email off the wire would take a lot more effort than somebody at Facebook reading your posts, and moreover has to be done while the email is in transit.
Email has the option to provide more security through encryption, and is less dependent on a single company.
For communicating anything of importance to my friends, I prefer phone or email, in this way I'm pretty sure that they'll receive it. To Facebook I post chit-chat and interesting tidbits for which I don't care who reads it and who misses it.