According to Lifehacker, a new Facebook feature allows you to translate posts and comments on Facebook pages.
The “translate” link is shown when a comment is made in a different language. It’s placed right next to the “share” and “like” links. Whilst the service is currently only available on Facebook pages, there are plans to roll it out to profiles also.
Facebook uses Bing to translate the comments, so as with any machine translation there will be errors. It will certainly save some time copying and pasting into a different browser window though! This may also be a handy tool for language learners looking for interesting content in their target language. Facebook has a lot of fan pages, events and interest groups, so it should be easy to find content, read it and then check your understanding using the translate feature.