Additionally (at least for the IE example) there's another huge difference: those who wished to use an IE alternative could do so and continue to engage the sa

Additionally (at least for the IE example) there's another huge difference: those who wished to use an IE alternative could do so and continue to engage the same activities and access all the same content--with a few ActiveX exceptions--as they could before. Most importantly, those who wished to make the switch from IE to Firefox or Chrome or Safari or Opera, etc. could do so without requiring any additional action by others. Again, outside of a few compatibility issues on a few sites, I could change the software I used without convincing webmasters or other users to do anything. Same went for webmail. I could switch to Yahoo or Gmail or Hotmail or whatever I wanted without requiring me to convince every other relative, friend, and business contact to do the same. With something like Facebook, you can't just use a different platform to interact with those same people in the same way unless you convince them all to migrate with you. If everyone you know only wants to use Facebook, then that's your option. You can't set up your profile on Diaspora or Google+ or whatever and expect to enjoy all the things you prefer about them because there's no shared protocol like there is with web browsing or email.