Which plugin does this Facebook job please?

Hey guys and gals,
I have automatic blog updates sent to Twitter and Facebook via LeenkMe and what I’m finding is that people are commenting there and not on the blog 🙁 What I need is a plug in that grabs those comments and copies them back to the WordPress post? Problem is I’ve spent a few hours going through several pages and not really knowing which one is the best. Any ideas or plug ins that people can vouch for please? :)\

Thanks in advance! 🙂