Here are a few examples of it on the site.
Some test comments, so you can see how they look:
When you post, you have the option to have the comment appear on your profile. While we certainly encourage this, you can turn it off if you’ll be leaving a lot of comments on files so that you don’t clutter up your Facebook stream:
If comments had been left for a file using the previous system, we’ve included a link to those so you can still view them:
Lastly, we know that some of you don’t use Facebook and have no desire to, and that’s perfectly fine. If you’re not logged in to Facebook, you can still leave a comment without any problems.
So there you have it. If you have any thoughts, questions or problems, please let us know.