4 ms·I figure there's no room for Facebook to grow with 500 million users - unlike Groupon at 25 million.by zandorg 16y agoI figure there's no room for Facebook to grow with 500 million users - unlike Groupon at 25 million.aero142 16y agoEven without growing the number of users they have, they can certainly raise their revenue per user, which is the big question as far as I can tell.zandorg 16y agoFacebook or Groupon?aero142 16y agoFacebook.