Facebook apps using the current Open Graph API will break on April 30, 2015. Facebook emailed iPod and iPad developers to explain why their apps will break if they wait until the deadline to upgrade to Graph API v2.0.
Now I don’t have a master’s degree in Natural language processing, and you just might need one to get your hands dirty with this API. I see the text-processing.com API as offering a mid-level utility for incorporation in a web app. You might take text samples from your source, feed them through the Text-Processing API and analyze those results a bit further before presenting anything to your user.