In a new interview with PCPowerPlay, Pete Hines was asked what measures did Bethesda take to prevent leaks and he said:

"Hope. There’s no special… you tell as few people as possible and you hope nobody says anything. There’s no magic formula to avoiding anything."

- On the recent gameplay footage leaked online he calls it a consequence of social media and the rise of video sharing platforms:

"Everybody wants to be, not everybody, they want to be PewDiePie 2. ‘I want to have tens of millions of followers on YouTube and make money doing it and be an internet celebrity,’ so they’re always looking to be the source and dig up information they can put out. It is what it is. At the end of the day, you have to hope that the people you’re working with value and respect the team that they’re working with and the thing they’re working on enough to keep their mouth shut and wait for us to talk about it and do it in the right way."

http://www.cinemablend.com/games/Simple-Way-Bethesda-Kept-Fallout-4-Secret-82237.html

Full interview:

http://www.pcpowerplay.com.au/feature/interview-pete-hines-on-fallout-4,408572/page0

So keep things tight and kneel down in prayer for no leaks.

Now if only the rest of the industry would follow Bethesda's example in this case we wouldn't have any of the so called "delays" ...

I'm pretty sure the Boston location was leaked a while back. Don't know about anything else though.

Props for keeping a game under wraps that everyone knew was coming.

The article mentions that leak:

The only pre-announcement leak happened about two years ago when someone released voiceover scripts from the game. These scripts revealed the Boston setting from the game along with a few characters. I suspect a lot of fans were suspicious of the report, though, due to some of the widely publicized Fallout 4 hoaxes that happened around the same time.

There was a leak by someone who got fired, ironically enough, for leaking information about Fallout 4. As someone who was fired, though, and with nothing to back up her claims, not a lot of people paid much attention. Also, she seemed stupid and petty, which only served to discredit her validity. Which is good, I'm glad it didn't get much press.

I hope games go down the Fallout 4 route when it comes to release dates.

I'm surprised their grammar almost has as many errors as their games. What kind of weird sentence structuring was that?