John, Rails is far from the only web app framework for Ruby. Other competent ones (i.e. used in production) are Nitro and IOWA. Several others exist which are probably little more than hobbies. That's not to put them down: some of them showcase excellent techniques and are an important part of the ecosystem.
Anyway, just wanted to clear up that misconception. Rails is, IMO, the best webapp framework for Ruby in every way, and it's certainly the dominant one, but it has prospered _despite_ being one of many choices. It wasn't a Ruby community effort to present a dominant framework to the world; it was the hard work of one person.
The "too much choice" argument regarding Python web programming has a valid point, but it's not fully convincing.