Behaviour or test driven development?

Dave Astels thinks it is important to change our idea of test driven to behaviour driven development. http://daveastels.com/index.php?p=5

Brian Marick thinks we should ask users to provide examples rather than tests.

Gerard Meszaros writes Unit tests to reveal object behaviour.

We write Functional tests rather than Design tests. It makes refactoring easier.

Which is right?

Well all of them provide focus on different aspects of the testing/behaviour of the system. They are all revealing the importance of different aspects of test driven development. Why do we need to choose one? Really, we don't. At different times each of them will become important.

Sometimes I want to describe the behaiour of the system. Sometime I want an seminal example of the system. Sometimes I want to drive my implementation. Sometimes I want a regression suite. They are all important at different times.