Here's my take: it's a good book, but a little long on the narrative since the essentials are right up front: 8 leadership steps towards change management.
Now, admittedly, this is more aimed at the business readiness swim lane, and the foreplay necesssary to get the business and the customer ready, than it is aimed at some of the change management tactics for scope control. Nevertheless, here's my paraphrase of Kotter's 8:
1. Put a value on short term versus long term
2. Gather a coalition of the willing
3. Develop the vision, goals, and strategy
5. Push action to the practitioners
6. Be incremental
7. Consolidate gains
8. Leverage culture
Now, in Kotter's actual formulation for point #1, he wrote more about creating a sense of urgency than simply putting a value on the short term. But, actually, I'm not a fan of crying wolf on urgency just to get the team moving. Frankly, I'm more about finding a legitimate reason to value a short term goal; with that in hand, you should be able to get some action going.
His point about #5 was the ole "empowerment" thing. It was probably less worn in 1996 that it is 15 years later. The issue is that the empowered may not know how to use their power. That hasn't changed since power and empowerment were invented:
Those with the power have no experienceThose with the experience have no power
General Sir John Dill
Placentia Bay Conference, August 1941