Sony Details Game Sharing And PlayStation Plus On The PlayStation 4 With A Handy FAQ
Users will be able to log into their accounts on other PS4 consoles giving them full access to download and play their library of downloadable games while logged in. There will be no limit to the number of consoles on which you can remotely log into, but you must be logged into your account in order to play the downloaded games on secondary consoles. You will also be allowed to be logged in to a limit of two consoles simultaneously.
Some PlayStation Plus subscription benefits will extend to all users on a single console. For example, if you have a PlayStation Plus account (necessary for online multiplayer on the PlayStation 4), other members of your household who play on separate accounts on your home console will also be able to play online multiplayer. They will also be able to play the games downloaded on that account. In order to do this, you just have to assign your home console as your primary console.
You can check check out the full FAQ here which goes into more detail, and reveals other small details about how users will interact with their PlayStation 4s.
This isn't too far removed to how things currently work on the PlayStation 3. It's especially nice to learn that some PlayStaiton Plus benefits will extend to other users on the same console. As someone who lives in a household where multiple login accounts exist on a single console, this is good news.