I just finished reading Scott Berkun's new book, The Myths of Innovation (O'Rielly 2007).  

While taking on the role of myth-buster; Scott provides insights into how innovations really happen and more important how they gain adoption. Like his first book The Art of Project Management (O'Reilly, 2005), Scott witty style makes the book easy and enjoyable to read.   There's much in the book that makes you rethink and question the common views of innovation.  While each chapter presents good insights, I especially liked chapter 9 "Problems and Solutions."  Scott does a great job pointing that the real key is correctly defining and framing the problem.

Some relevant quotes:

Problem solving is not nearly as important as problem finding.

Problem finding--problem solving's shy, freckled, but confident cousin--is the craft of defining challenges so they are easier to solve.

Discovering problems actually requires just as much creativity as discovering solutions. There are many ways to look at any problem, and realizing a problem is often the first step toward a creative solution.

I guess this brings us back to the Problem Space vs. Solution Space discussion Earl Beede started on Construx's Requirements Forum.

I highly recommend this book. It's a short easy to read book; one that will keep you enterained during a cross-courntry flight.