It seems he got the boot...

The New York Times confirmed the firing, along with the unrelated ouster of Apple's new retail chief, John Browett.
The Journal reported that some within Apple considered Forstall a divisive figure who "never fit into the culture at Apple," and who had long rankled other company execs but enjoyed the confidence of Steve Jobs.

"If it turns out that President Barack Obama can make a deal with the most intransigent, hard-line, unreasonable, totalitarian mullahs in the world but not with Republicans? Maybe he’s not the problem."