While working on a project last year, I needed to educate my client on what a taxonomy is, how it fit in with the ubiquitous word "metadata," when to use a taxonomy. The client also wanted to maintain their taxonomy on an ongoing basis, without my input, so I needed to give them the tools to update it themselves.
This morning I had the pleasure of reading Nathaniel Davis' articles. You might ask why I was so excited to see these articles and I'll tell you. It solidified for me how I've always felt but could not put into words: that IA is not about interaction design (or even wireframes) but is about information organization and strategy.
While working for Rocky View County in Alberta to help them redesign their website (not currently available), we held an on-site kickoff meeting that included two sessions of card sorting. These sessions went rather well and included some facilitation on information and content needs and the card sorting facilitation.