Facebook slid some new location sharing features in its 11.0 update for iOS today, despite saying “What’s New” was only reliabity and speed improvements. I dug through the app and found Facebook is trying to get more people opting into and using its new ambient proximity tool by adding a search box and invite button atop the Nearby Friends screen. Facebook may be attempting to grow Nearby Friends quickly in an effort to box out its new direct competitor Foursquare Swarm.

After I asked, Facebook confirmed that these new features exist, but that it only puts things in What’s New if they’re available to everyone. Nearby Friends is still rolling out and is US-only.

Facebook launched Nearby Friends in mid-April. It lets you constantly share the current neighborhood where you are and the approximate distance between you and your friends or whoever you authorize. It also lets you share your exact, real-time location with specific friends for a few hours or indefinitely. The feature is designed to make it easy to meet up with friends. [Disclosure: I advise a college friend’s stealth social location-sharing startup codenamed ‘Signal’.]

Since the Nearby Friends feature has major privacy implications, Facebook did the right thing by making it opt in so users have to purposefully activate it. The problem is that Nearby Friends is already buried in the More menu of the app, and then gated behind the opt in. These are surely hindering growth.

To give the feature a boost, Facebook now displays a ‘+’ sign in Nearby Friends that you can tap to invite friends to activate it. Recipients receive a push notification asking them to turn it on. Facebook likely hopes that social proof and friend-to-friend recommendations will convince people feature is worth giving up some privacy for.

Once people are signed up, Facebook wants to make it easy to find specific friends whose locations you want to see, so it’s added a search bar. Typing in a name brings up their approximate location, distance, and option to give them your exact location if they’ve opted in, and a button to send an invite if they haven’t.

These new features highlight how Facebook’s troubled history around privacy is coming back to bite it. Had it been less cavalier in the past with auto-sharing features like Beacon or changes to privacy settings, it might have been able to get away with making Nearby Friends opt out. Instead, it was slapped by the FTC with 20 years of privacy audits and a requirement that new features that change privacy controls be opt in. You might call that privacy karma.