It was announced by Facebook on Friday
Starting today, in addition to your other activity, you’ll be able to see the searches you’re making on Facebook. Just as you can choose to delete any of your posts, you can use the same inline control on Activity Log to remove any of your searches at any time. It’s important to remember that no one else can see your Activity Log, including your search activity.
What’s interesting is how Facebook positions this. They are saying that you can remove your searches. Translation: We have been tracking your searches for a while now ad before we get jammed again for abusing your privacy we are going to put out this preemptive strike.