O'Reilly publishes first game-engine specific HTML5 Book (on Impact.js)
O’Reilly media has published one of it’s world-renowned Animal Cover books on HTML5 Game Development titled:
Introducing HTML5 Game Development
Developing Games with Impact
It’s a short book (120 pages) but it marks a milestone in that it’s the first (to my knowledge) paper book published which is entirely targeted a single Engine in the nascent HTML5 Tools Space.
Impact.js was one of the first HTML5 Engines released and has been getting better all the time.
You can grab the book in both Paper Form