I watched Part 1 of this great lecture, and I just had to share:

  http://architects.dzone.com/videos/dci-architecture-trygve

You can read my brief post on it here:

  http://proutils.github.com/2010/02/dci-architecture/index.html

I love the line "Code must be Chunkable". Reminds me of _why.

Also some interesting counter arguments about TDD.