Facebook is addressing one of the biggest concerns over Facebook Login today in an update that should allow users to prevent apps from spamming their friends. All apps that allow signing up through a Facebook account will now be required to ask users if they want to have stories — be it the songs they've listened to or how far they've run —automatically shared back to Facebook. If the user doesn't allow it, the app won't be able to share news items without permission, though users will still be allowed to share individual stories on their own. It may be a common sense update, but it could mean that fewer people will ultimately be sharing stories to Facebook. Even so, having users sign up with Facebook in the first place still means that they've connected their account, and that's one more person with an easy way to share.