[adrianhoward]

I'd add it:

* user observation and interviews

* a/b testing

to the list of tools.

(Indeed - the whole discussion is framed in the context of 'the product launch'. With a chunk of my clients that's just a dead concept. They're trying out new features with small chunks of their market at many different levels of fidelity all of the time. Not everybody can do this - outside of the context of web applications/sites it gets much harder - but if you can escape from the idea of the product launch everybody's lives seems to get much simpler)