An excellent refresher for those who facilitate brainstorming sessions and Rapid Design Labs.
I particularly liked the way that game theory is framed in a simple, easy to understand way and how it applies to idea generation for business. It turns out that I've been using a bunch of these techniques for years (card sorts, affinity mapping, dot voting, post ups), but I also found some of the tips and explanations very helpful - turns out I'd been doing some of them wrong, or at least not quite 'right'.
I also liked the thoughts on how to employ visual language to communicate ideas. The visual alphabet reminded me of Ed Emberly's work.
The catalogue of exercises is great. It would be super if they produced a set of flashcards similar to IDEO for quick reference.
I'll be keeping this book handy.