Logging into apps and services with Facebook is really easy—but it's also really creepy. You don't want to just give up a ton of permissions you don't trust and don't even necessarily know you want to use more than once. At F8, Mark Zuckerberg announced some forthcoming improvements to Facebook logins that make it way better.
Currently, Facebook allows you to determine two types of access to your account: read and publish permission. One allows an app to see your information, the other allows the app to publish to your friends. Today's changes give you more granular control, so that you can determine exactly what data the app gets. Obviously, some apps won't work very well (or at all) without some data, but it's nice to have control so that you're not needlessly spewing information to random developers.
Additionally, Facebook will also let you login to apps anonymously so you can check it out before you decide to link your account to some weird app.
Overall, the changes are definitely a privacy improvement from a company that's notorious for not respecting your personal information. [Facebook]