Unlike fragrances and clothing, nobody (very few?) chooses their email app based on a personality. The celebrity link is just too vague; it isn't "Marissa Mayer

Unlike fragrances and clothing, nobody (very few?) chooses their email app based on a personality. The celebrity link is just too vague; it isn't "Marissa Mayer's Yahoo!", it's just Yahoo!. Even if it was, millions more people look up to Kim K or Paris H. Also, the investment is way too high to be celeb-driven. It's easy to buy a perfume or a purse or suit or shoes because you like the link to $CELEB. But switching email providers or default search engine? Never happening.