I've realized how much the hyperlink has been devalued, almost made obsolete.
I disagree. Maybe it's just my personal usage of Twitter, but the tweets I read very often contain links. Some of them exclusively. I follow people on Twitter who filter the net, tweeting interesting links. The same thing still happens on regular blogs, of course. With both groups of people I trust their judgment and value the time they spend sifting through numerous articles and just posting the interesting stuff. The same principle as reddit, Slashdot, and so on. The web is large, and all those people and services help me with orientation.
Of course there are other types of tweets. "Real" discussions about issues. Calls for action ("support my charity!"). Sharing information ("Four more years.") Snarky comments. Fun stuff. Diary-type entries ("had coffee at Starbucks").
I can reference people by their Twitter handle, and they will notice (if they care enough). It's easier than following discussions on numerous blogs, it all happens in one place. At the same time, that is also a problem. Twitter treats their data as a walled garden. It's really unpleasant to provide a third-party client. In that sense it's the opposite of Usenet.