"An interesting consequence of this, by the way, is that only about 10% as many Facebook engineers as Google engineers are reading and responding on a "smackdown" thread like this one; you should bear this in mind when skimming them."
Well that's interesting, because I count 1 Google employee vs 5 Facebook employees. Did this thread get sent out on an internal Facebook mailing list or something? Several are new users.
Google:
http://news.ycombinator.com/item?id=4824681
Facebook:
http://news.ycombinator.com/item?id=4824909
http://news.ycombinator.com/item?id=4824979
http://news.ycombinator.com/item?id=4824964