The comments are from the USA Today CEO Forum in Atlanta, which happened over a week ago, but they were only published today on the newspaper's website. The Q&A was "edited for length and clarity," so unfortunately we don't know if there was any relevant context to the questions.
Google CEO Eric Schmidt was recently asked a similar question, but he said that neither Facebook nor Apple were Google's biggest competition. Instead, he said it was Bing. Of course, Yahoo is now powered by Bing so of course Microsoft is more friend than foe. Still, it's interesting to see that Google completely denies Facebook being a competitor while Yahoo says that it will be one day.