If you are deep in developing your app, and the time comes to look at Facebook and OpenGraph, you might find yourself on a stumbling block I came across last night. The annoying part happens due to the fact that Facebook caches the results of your page. And this really gets in the way of testing changes. In fact I’m not really sure how long this cache even lives for. What I’ve found to be quite helpful Facebook’s URL Linter. This forces a reload of your data and removes the cached copy, and you will be able to see the changes in your app a lot sooner. The tool doesn’t just reload cache, rather it’s there to let you know if you have any issues with your code.
Perhaps I’m the wrong type of developer, but I sometimes like to see the minor changes in my code I test as I go along. I’m not able to visualise multiple changes so easily. So if you are like me, give this a whirl ! We found this tool via a post from developer blog post by Paul Tarjan this time last year.

Edit : see below in the comments for a better alternative.
