I'm sure someone has said this better than I will, but here's my little rambling of the moment...
Back before the internet was invented, before 1990, we connected via bbses and modems. We connected from our computers to another computer pretty directly. When we connected to the site it was pretty obvious what we were connected to, who was in control, and what our limitations were.
Then in 1990 the World Wide Web was invented and we started to connect with things like AOL, CompuServe, the Spa (which was a bbs but then evolved), EarthLink, and others. When we connected this way it was still pretty obvious when we made our connections who was in control, where our email was stored, and where our "home zone" was most of the time. Even back around 2000 (give or take a year or two or so) AOL tried to be everything it could be. When I had an AOL account I sometimes did all of my searching and surfing through AOL. AOL could easily track my activities and that kind of seemed obvious.
Now... things have been changing a lot during the last 20 years... we have Yahoo and Gmail. These are not something that we connect to. We connect in other ways. I use Wildblue. A lot of other folks use Verizon or Comcast, or they use smartphones. (I haven't gotten as far as smartphones yet since we don't have cell phone service at our house). With Wildblue we don't even see the connection. It's invisible. We are immediately shot out into the internet universe. We can go where we want to go, see what we want to see, and who is in control? I don't know.
With this new invisibility comes... Facebook and Google and others... it's like a light switch went on and they realized "no one is in control anymore...." and they want to be in control. Facebook wants to be the "new internet". Google is trying to compete sort of, only Google is really trying to do it all. Google wants to be your search engine, your blog host, your email, offers you word processing and publishing, storage, and now social networking with Google +... etc, etc... I just saw something this morning about "Google sites" which looks to me like "creating a page" on Facebook for a group or special event or something... To be clear Google has gone way beyond Facebook on many fronts. Facebook has been a social network traditionally and now they seem to want to branch out. Google has been everything but a social network and is now trying to be that too. It's just crazy.
It seems like we're coming around full circle though. We're not quite there yet, but it seems to be moving in that direction. We used to know clearly where we were, who had access to what we were doing, and who was in control behind the scenes. We lost sight of that for a while, but now I think it's coming back into focus. Only now people are not sure they want it. It will be interesting to see where the future goes.