Yup -- I went looking for a piece I wrote around that time.
http://scripting.com/stories/2009/06/05/formatsAreLikeTreesM...
It was a response to TechCrunch saying RSS is dead, and Twitter's protocol was the new thing.
I was sure they were wrong because of the same thing we're observing about PG's piece.
The protocols last forever, it's the companies that die.
I remember that leak very well as I was part of the MSFT team that had the 'deep infrastructure deal' meeting that is mentioned in that post. It was an interesting time for Twitter - Ev had to leave early because he was flying out. I learnt later that it was to appear on Oprah.
Such a stark difference between then and now.