People can't change that radically. However the tech is going to be designed differently. That argument that happened before snowden where someone would tell the security expert he was being paranoid... that will go differently.
Corporate America is also taking the security more seriously. After Target and Sony they're starting to understand that they have to take this seriously... or else.
This. Security will be taken a little more seriously, which helps a little. There will be a *little* more oversight and pushback within government, which helps a little. It's not a fix; it's patch. What we're seeing is very similar to the response that small companies tend to make to a major security breach--they plug that particular hole, they tighten security a little bit, and they respond a little bit to public concern. It's a net positive but still not enough considering the risk of abuse of mass surveillance.
We only have evidence that they're abusing it a little bit right now--like for parallel construction, which is flagrantly unconstitutional. The concern, and the time when we'll see people more thoroughly changing their habits, will be when (1) people realize their phone calls are being coded or recorded or listened to (this will freak out EVERYONE on wall street, who make phone calls when they do illegal things), and (2) the government starts publicly using some of the information it collects to charge people, discredit people, or target people for being disappeared and people realize it.
That's how it works in the tyrannical states. We're not there yet, but we've been close in the past (think McCarthy or Hoover and what they could have done with this mass surveillance apparatus). We have a lot of great guys in intelligence and I hope that continues to be the case--but without strong institutional safeguards, that's not enough to count on.
Now our government could use the information more subtly, just to influence events by digging up dirt on key players. That will be much harder to stop and is less likely to change public use of the communications infrastructure.
I mean, do you seriously believe that the NSA doesn't have dirt on every single presidential candidate? They may not be using it out of respect for the integrity of the democratic process or out of knowledge of how bad the blowback could be, but still.