Facebook's Sympathy ButtonFacebook's Sympathy Button
Facebook now seems to be planning on adding a sympathy button in addition to its like button.Their primary aim to provide the users to express their emotions on a particular post of their friend.
There will be no captions on that button, but it is primarily based on the traditional 'mood' drop down lists that is in use now. It is likely to be updated by next year beginning.
And FB just recently launched dislike button for the FB messenger, and soon it will be releases for the Facebook chat too. :)