The book has a really great mix of the theoretical (gestalt theory!) and the tactical (stacking graphs!). In fact, if there is a flaw with the book, it’s that it tries to cover too much–data visualization, information architecture, visual design–and does so in a lot of depth. It makes really important nuggets hard to find.
I would have also liked to seen some overview of the UI patterns presented. I’ve never been able to formally put the UI patterns into practice in my own design process. An overview diagram (big overall patterns down to tiny discrete ones) would be really helpful in that regard.
Puzzling to me is why, although it appears to be selling well, this book hasn’t gotten the wider reading (or at least discussion) it deserves among the interaction design community. I didn’t hear about it until months after it was published (November 2005).
Side note: I’m also stunned at the amount of examples Tidwell is able to show. I’m in the middle of tracking down permissions for my own book, and it is a nightmare getting people to get back to you. I’m not sure how she got such a vast array of examples: big names like Apple, Microsoft, Amazon, and Google.
In any case, a strong recommendation. A book I expect to reference for a long time.