I used a version of it 7 years ago called "socialcast" now owned by vmware. it's a little more organic than a wiki or confluence for knowledge repo, but because it's so much easier to get input, the quality of the input isn't nearly as good. I'd definitely not use the actual facebook product but something similar you can host yourself or at least encrypt with your own keys.
if your company is old enough that it has an established knowledge repo, this is probably a waste of time
[Edited on January 24, 2017 at 12:58 PM. Reason : ed]
1/24/2017 12:57:48 PM