This took me all morning to figure out. I’m posting here so there is clear information on this subject in at least one place on the internet.
The situation is this: when targeting iOS6 using Cocos2d-x v2.0.2, there is a bug in the auto-generated “Hello, World” code that shows up in a fresh project such that the compiled game will not display in landscape orientation even after following the steps in this item from Cocos2d-x documentation (such that it exists).
The solution is to follow the steps enumerated in this note from Walzer Wang. This fix is probably already in v2.1 but 2.1 is still beta, as far as I know, so this issue is probably still in a lot of code out there…