Facebook graph search has raised a lot of legitimate questions about the privacy issues of its users. Here’s one from Wamda about potential threats in the Arab region. Information you have posted publicly on Facebook will make you searchable, such as post updates, pictures, pages you have liked, etc.
Electronic Frontier Foundation has just produced a guide on how to change your settings to protect your privacy from graph search. We recommend that you read it to be aware of the threats to your privacy, and to be able to decide whether you want to be included in the graph-search fiesta or not.