Facebook has implemented a new EDIT feature (that offers audit trail) … Originally, posts were locked down so that likes or responses would be in line with original posts (primarily to prevent pranksters from changing content of message to the opposite meaning)
QUOTE: you’ve ever posted something on Facebook that you’ve immediately wanted to tweak or correct, Facebook has a solution for you. This week, the site announced that it would roll out a new feature for its web platform and Android Facebook app allowing users to edit posts and comments. Facebook, a lightning rod of privacy issues lately, has already addressed many people’s primary concern with this feature. Facebook will mark posts that have been edited and allow users to see a history of the changes made to the content. This will prevent users from being suckered into liking a post that is edited after the fact.