Now I know what a 'like' is on Facebook, but as someone who doesn't centre their life around Facebook it also means other things to me, like 'similar'.
At the current count there are 1179 questions tagged with like. Of those, 520 are also tagged facebook. This leaves 659 questions that are not Facebook related. There are already 2090 questions tagged with facebook-like.
Here is a link for those willing to help in the clean up (there are currently 649 still to be done).
(Note that this is a follow-up question to this one from just on a year ago: The “like” tag is used for various meanings.)