Apple's BrandIndex numbers are significantly higher than the average of the 1,100 brands that Marzilli's team tracks on a daily basis: The median Buzz score is just 4 among 18- to 34-year olds (versus Apple's 27) and only 5 for the 35-and-older group (compared to Apple's score of 31).

"It's only natural," Marzilli said when asked to explain the downward trend of Apple's score since January 2008 among younger consumers. "The iPhone and iPad have more competitors now. Those rivals are vying for the same audience, so I can see early adopters exploring other possibilities. Some of them may find a new home with a Samsung or Kindle."

The rising scores expressed by older consumers point to Apple as a mainstream brand, Marzilli argued. "There's nothing wrong with that, in fact it has obvious advantages," said Marzilli. "Microsoft has been mainstream for 30 years. The key is to be both mainstream and still perceived as cool and innovative, that's the ideal."

Marzilli declined to speculate whether Apple knew that its customers were aging, or at least that older consumers thought more of the brand than did younger ones, when it planned the oft-knocked ads.

"I don't know if I'm making Apple look smarter than they are," said Marzilli of the conclusions reached by BrandIndex.