Facebook recently released its Social Graph Search. Despite its horrible name, its a very powerful search engine for Facebook. Already privacy advocates and others are freaking out due to the very large and previously hidden by obscurity amount of data it unearths.
Facebook has largely been a browsing service where you scan a timeline of data. There is only so far anyone is going to scan, so after a few months whatever you have posted fades into obscurity. Now with a powerful search engine, all kinds of data, no matter how old can be found and displayed. This is primarily what has people concerned. Some people are going back through their data and removing posts and unliking pages that could be embarrassing.
I have always had a social media golden rule: Don’t post anything you wouldn’t share with anyone.
Remember, you don’t control these social platforms and you can never know what changes may come that could change the equation. Be thoughtful and careful about your social media actions and you will not have anything to fear.