I was stumped by the "really different faces of the same thing" claim as well in relation to HTML and RSS.

While RSS is not dead, and probably wont be for a long long time, I also think it needs to be viewed in perspective. "normal" people (not you and me) don't know what RSS is and for the most-part don't use it (or don't know that they are using it sometimes).

Dave has some good insights from time to time, but I get the impression that he is stretching his credits and claims far beyond reality.

You can only wave the "I co-invented RSS way back" flag for so long.