I had a bug where I would call to transitionWithView and the new view would appear in Portrait while my app and all XIBs are only marked as Landscape as well as the origin view.
I found how to fix the problem thanks to this question (+1) :
I would like to understand though ( and it is not explained there ) - why does it behave this way ? Where in the application is the orientation stored, when is the view notified about the orientation and why views which are transitioned to are unaware of the orientation vs views which are added using addSubview...
Searched a lot but did not find clues . thanks