I haven’t really spent a lot of time with RSpec since about the 0.5 release. I took a tutorial class with Dave Astels and got jazzed about the opportunity since they were really able to leverage Ruby to make a nice BDD framework. After using RSpec all JUnit test methods started including should. The Rails integration back then was a bit flakey and I just dropped back to Test::Unit.
Version 1.1.2 plays nice with Rails and the momentum of RSpec has definitely picked up over the past two years. Spending time using Story Framework looks compelling as an option for specifying functional/acceptence/customer tests.