Both Apple and Google saw their CEOs stepping into the background this month, for different reasons, but there was still a sense of an old guard standing aside. But the change is likely to come from outside. Apple and Google, two of the companies that have helped define the new web age ‘ once the closest of allies, now bitter enemies ‘ will not be steered onto a radically new course by their new operational chiefs. Indeed, to the disappointment of some observers, they have stuck firmly with the old guard. Apple COO Tim Cook is reprising his now-familiar role of standing in for Steve Jobs while the CEO takes leave for health reasons (though he remains involved in strategy…