Guys like Balmer are not motivated by money any more. Balmer had enough money to retire by 1986. Steve Jobs was not motivated by money either. They like competing and trying to make their companies successful.
If there is indeed an iphone 4S there is no way there will be an iPhone 5. If they were the same price everyone would buy the 5. If doubt they would upgrade the 4 to a 4S and offer it as a cheaper alternative to a 5. Apple uses old models as the cheaper phone. Apple will launch one model: the iPhone 4S. And we will all skip it and wait until 2012 and buy the iPhone 5LTE.