Facebookers have had their own versions forever.
He probably wants to offer a “less offensive alternative” to all those.
Having a "dislike" button will add more detailed information to a person's profile, thus making that person a more fully and accurately defined person for advertisers to target and for government agents to profile. Employers will be able to better identify traits a person has that are undesirable. Trends will be more quickly identified, exploited and manipulated for corporate profit and to direct messaging that influences people. Facebook will make billions more with these more closely targeted profiles of people.
Yeah, it's all good. (sarcasm)