Let's talk testing!

We're super productive with Rails and JavaScript MVC libraries, but it seems harder than ever to write tests for our apps. I'd be happy to talk about my experience going from a chaotic test-free environment to full TDD, the times when testing is useful and when it's wasteful, and the tools and techniques I use to test-drive Rails + Backbone apps on a daily basis.

Is this interesting to folks? Is Wednesday a good night?