Indeed: the story (http://www.techcrunch.com/2008/05/01/twitter-said-to-be-aban...) now has an update:

"Update: Regarding Evan Williams’ statement here [link to http://twitter.com/ev/statuses/801530348], all I can say is that multiple sources claim that Twitter is telling people they are planning on moving away from Ruby on Rails. This is not the first time a company has denied something that has turned out to be 100% true."