Just to play devil's advocate here: for almost everyone in the non-techie general population that I've seen use the Internet, Google's search bar IS the address bar.
They want to get to Facebook? They type "facebook" into Google and click the first link. They believe that Google is how you access the Internet, clinging onto the old AOL frontpage mentality of portals and site discovery. That's why search ranking matters so much.
What's funny is that even people who never used AOL or Yahoo! (the early version :) still do the same thing, which I think says more about the cognitive load of browsers, domain names, bookmarks, etc, than it does about Google. Google makes all that load just disappear.
Then educate those people and don't push for some nanny-state mandate by which even if the freedom to switch services is available one service must freely advertise all the others.
Not to mention the hypocrisy of Facebook/Twitter blocking data from Google yet they are demanding to be featured anyway.
They want to get to Facebook? They type "facebook" into Google and click the first link. They believe that Google is how you access the Internet, clinging onto the old AOL frontpage mentality of portals and site discovery. That's why search ranking matters so much.