(Uh oh, Ruby guy here, avert your sensitive eyes!)
Interesting thread, and I agree with the prediction that the Ruby web framework community will fracture, and history will play out, a little bit. It'll be a test of Matz' little language to see what happens from there.
I just wanted to point out a few things for those who might be observing the conversation from the outside. Rails has always been developed as an integration of several separate, isolatable components (ActiveRecord, ActionPack, ActionMailer, ActiveWebService, and possibly ActiveSupport), and while those components mesh much more closely with each other than with outsiders, they can mesh outsiders. Two examples:
Though, maybe I'm way off here, and should go back to my hole...