Q: Aren't URLs just so, well, clunky and clinical, compared with good ol' Twitter @names?
Definitely. But what we're seeing here are good ol' blog posts, which are sent as HTML. So Tim Carmody could just as well send "@jennydeluxe" a mention by writing a post which stored thus in HTML:
Terrific story by <a href= "http://twitter.com/jennydeluxe"> @jennydeluxe</a> on Hana Beshara: <a href="http://www.nytimes.com/ 2014/09/28/technology/the-unrepentant- bootlegger.html">nytimes.com</a>
which would be displayed, of course, as