I picked up both of these books since they looked pretty similar and I couldn't decide on which one to get. I've gone through about half of Osmani's book, and have just started up Stefanov's book, and so far I'd have to recommend Stefanov's.
One of the first set of patterns I learned were the Module/Revealing Module and Prototype/Revealing Prototype patterns.
The code that I had been writing was working, but I had this nagging feeling that it smelled- especially when I was trying to tackle more complex situations. The more code I wrote, the messier it was and the harder it was to maintain/debug. Spaghetti is yummy, but spaghetti code is definitely not something I want to serve.
Anyways - I wanted to share this series of videos which really helped to speed up my understanding of the Module Pattern.