Derek Thompson outlines it:
According to this chart — adapted from a Mary Meeker slideshow excerpted by Bill Gross — we spend more time engaging with mobile devices than reading print. But print publications still get 25-times more ad money than mobile. Either the eyeballs are moving faster than the advertisers, who will eventually stop paying for print … or the ad teams don't think a minute spent around mobile ads is worth a minute spend around print ads. Those aren't mutually exclusive.
Jeff Sonderman has more.