37signals are such stuck up, elitist, preppy twats... They should eat their own words and compete.
This was just a demo app for a framework in a completely different language. I don't think it was a huge threat, I mean come on, they didn't invent online chatrooms. They just invented a doll house, my Mom can play with, that looks like a watered down IRC (for $$$).
The main reason they sell Campfire is for the integration with their other apps... something I doubt the Google App Engine Team managed to add to their clone.