Yeap, except it's a complete different league. Cocos2D-X (which is the real cross-platform equivalent) is an absolute nightmare for beginners. Last time I checked, there was no documentation except in chineese, and you wouldn't even know where to look when you wanted to do some networking.
Unity truly is a marvelous piece of technology and ecosystem.
I actually bought "Cocos2d-X By Example Beginners Guide" and it was very easy to get up and running with a demo application. The samples included with the framework itself show off a features and nothing has been all that complex, and I have made a bunch of 2D test applications already (XCode + iPad simulator)
Thanks for mentioning this book, I've wanted to dig into cocos2D for a while but the lack of a good beginner book kept me from getting too far. I picked it up last night and it's exactly what I've been looking for. Awesome thanks!
The biggest problem I found with Cocos is trying to google for something. If you're developing for iOS, then it's fine. But if you're looking into, say HTML5 canvas, finding a working JavaScript example for something is like looking for a needle in a heystack.
This is one of the main reasons I gave up on Cocos and used EaselJS for my last project.
Unity truly is a marvelous piece of technology and ecosystem.