I love how it stops at YouTube, however Facebook and GMail/webmail definitely deserve to be included. Nothing else important happened after this. Maybe iPod, since podcast is already on the list.
Keith still post on the internet, specifically on Usenet or what's left of it.. see Google groups rec arts science fiction written or rec arts science fiction fans or something like that
The term described his vision of a VR-like, immersive "internet" of sorts. The book became a cultural touchstone for many reasons. For example, the Wachowskis cited it as a major influence of their vision for the Matrix.