Yep, and witness Rake releasing an update that breaks Rails, Rubygems releasing an update that breaks Rails, Rails 3 being a performance nightmare, gem authors nuking each others' namespaces...
I think in general that Ruby has one of the better communities out there (I'm a rubyist myself) but all this noise about TDD and cute DSLs (RSpec, Cucumber...) hasn't made a material difference in Ruby code quality compared to any other language.
Btw, Peter Norvig himself has good things to say on TDD[1]. So using him in an argument against TDD whilst he's using tests is kinda self defeating.
1. http://gigamonkeys.wordpress.com/2009/10/05/coders-unit-test...