Sony has already stated they are not

http://www.eurogamer.net/articles/2013-02-21-sony-tells-eurogamer-playstation-4-will-not-block-used-games

Sony has the tech, as we all know from the patent leaks, and it is seemingly the best way of doing it too where it wouldn't requre you to always be online. Yet I think this is a safety net, if things get too bad Sony will give Developers the option (as Sony would never want to be the blaming party themselves).

If the 720 blocks used games, and Sony gives developers the option, surely most will block on both. Also that article is mostly reassuring people that they can play their games on someone elses console, which gives the impression that games will be tied to accounts. I'm sure it would be easy for them to charge to transfer games.

Did they really?

Here's an extract of that denial:

"So if someone buys a PlayStation 4 game, I asked, you're not going to stop them reselling it?

"Aaaah," was Yoshida's initial answer, but seemingly only because he'd forgotten his line. "So what was our official answer to our internal question?" he asked his Japanese PR advisor. The advisor stepped in but didn't seem to answer clearly, at least to my ears. Yoshida then took control again firmly:

"So, used games can play on PS4. How is that?"

CAN PLAY, he said. In what manner? Can it play used games for a standard fee for your Sony account? An online pass per game?

If there were no string attached, he would have just said YES, without checking what answer to give. This is not a clear-cut answer.

Yeah, having those in the extreme sense that everyone seems to be saying will happen is very unlikely. Here is what I think is the possibility with all of these rumors.

1. They are implementing no used games and always online required as an option in their OS which would allow publishers to block used games if they choose to (and by default require the console to be connected to the internet for those games). I believe this is the most likely scenario.

2. Microsoft is leaking these rumors as part of their marketing plan to do the following: Make people think and talk about the next Xbox (bad publicity is better than no publicity; and this news isn't so negative that people will automatically say they aren't getting the next Xbox simply because of these rumors). By doing that, they making people also think less about the competition. And now that they have set the bar so low, anything they announce will sound absolutely fantastic.

It certainly has crossed my mind...I mean they couldn't be THAT stupid and arrogant and out of touch could they?