I've no horse in this race, but find the discussions interesting (and agree our previous attempts at reputation didn't work; our CD has said we are "much larger and less personal" than in those days, so FT is a somewhat different environment).
Here's Mark Zuckerberg on why a "Like" (but not other) button is available on Facebook:
YouTube video, and his prefatory comment.
Originally Posted by Mark Zuckerberg
Here’s a video from our Townhall Q&A today at Facebook HQ, where I answer the top voted question about why we don’t have a dislike button on Facebook.
For today’s Q&A, people flew in and submitted videos from around the world to ask questions ranging from our plans for improving search and why we update our privacy policy to how Facebook can help create stronger communities.
I appreciate the time so many of you put into asking questions and traveling to speak with us. Open discussions like this are an important part of our community, and a good opportunity for us to learn how to make Facebook better.