&gt; Because the substrates are open, users can relatively easily switch between centralized services,<p>How is it easier for me to switch from Facebook to something else, if it&#x27;s carried over the Internet as opposed to something proprietary like their own modem pools for example?<p>I can&#x27;t think of a single service for which that is true. Facebook is the lock in, just as Microsoft is the lock in for office PCs even if the underlying technology is somewhat open.