Fast Innovation : Achieving Superior Differentiation, Speed to Market, and Increased Profitability by Michael George, James Works, and Kimberly Watson-Hemphill is a great synthesis of current thinking on product and service development. Chapter 2 "How to Become Fast" isn’t about designing faster, rather it’s about how lead time and task variation cause delays in project schedules. Two "Laws" are introduced:

• Littles’ Law: Time-to-Market is inversely related to the number of projects in-process; the more projects you have, the longer all projects will take. The fewer projects you have, the faster the development process can flow.
• Law of Innovation Variation: Project task time varies and is related to percent utilization and number of cross trained resources. Delays stack up. Without slack time or off loading of critical resources projects will be late.

To me, some of the most valuable material is found in Chapter 4, "The Value of Thinking in Three Dimensions":

• product-service innovation
• market definition innovation
• process/business model innovation

I agree with them that although product and service innovation are the cornerstones of most innovation programs (e.g. Microsoft Windows and Voice-over-Internet-Protocol telephony), there are perhaps even greater opportunities in the other two dimensions, market definition innovation (which reflects the leverage possible from existing customer and supplier relationships) and process/business model innovation (which can create a competitive advantage that lasts longer than that from sustaining product or service innovations). The book isn’t a difficult read but will cause you to think, so if you don’t mind exercising your brain you might like picking this one up.