I like how they can target specific cities or countries of what you want your ads too look at instead if just looking in general places/cities where people are from all over world. We use them because we wanted our website content specifically tailored towards users who were visiting us directly form other social networks such as facebook vs google search engine results page (SERP) rankings which was not showing up well with their services so far! So now it shows better ranking than before but still needs improvement :).