It now seems clear that any and all electronic communications are grist for the NSA's mills. Only a fool would imagine that something expressed directly and plainly by phone, email, or SMS would remain private between sender and receiver. Of course, most of what we say to each other these ways is utterly trivial and inconsequential as far as the spy agencies are concerned, which doesn't mean, of course, that we are happy or even content to have our private communications, however mundane, so casually and routinely raked through.
Broadly speaking, there are two ways to go: we can, as some have urged — half provocatively, I think — learn to live in a post-privacy world. Human beings have done it before, as anyone who has lived in a village can tell you. Privacy as a legal concept is, after all, something of a late comer to the party.
Or we can learn to encrypt. This is something that lawyers, who are forbidden from village gossip, must now — as a matter of professional responsibility, I'd say — treat with all seriousness.
I know far too little about encryption to be able to say whether there's any hope of ever shielding information so securely that only an agreed-upon recipient can learn its true content. But I believe that there are techniques available to us that can make it onerous indeed for a spy to decrypt our messages. I would say that we will see a great deal of Internet attention paid to encryption in the near future.
It's started already. Slate has a piece on "How to Shield Your Calls, Chats, and Internet Browsing From Government Surveillance," mentioning among other things PGP (or "pretty good privacy") as a way to encrypt emails and Cloudfogger as a tool to encrypt files on Dropbox. I've learned that a South African company called Seecrypt offers to enable "military grade" encryption of your mobile phone calls and texts.