Yesterday (probably it would be a few days ago already) , there are people reporting problem in rendering the comments box social plugins. For details, see the post http://forum.developers.facebook.net/viewtopic.php?id=95474
This reminds me of the Facebook Beta Tier. Can those people reporting the problem catch this problem if they use the beta tier to perform regression test on their applications / website every week (or even every day).
I really can’t tell, as I do not use the beta tier. 🙂