Apple thrived this year despite more health problems for founder and communications icon Steve Jobs that resulted in him taking another sabbatical. He did make a brief reappearance recently to front the launch of iCloud, but the burden of driving Apple's communications has clearly fallen on the capable shoulders of his right-hand woman Katie Cotton, who has long been viewed as Jobs' "gatekeeper."
The Apple phenomenon is such that even when it made a snafu, which it did recently when a website went down unexpectedly, the public actually perceived it with excitement because they – rightly – viewed it as presaging a new product launch.
That's a powerful brand proposition, one Cotton has carefully cultivated while shunning mainstream communications techniques. As such, she merits a spot on this list – with or without her mentor.