Google's mobile ad firm AdMob in one of its rare post-buyout studies has revealed surprisingly rapid uptake of tablets. About 28 percent of those asked who had a tablet, most likely an iPad, were using it as their main computer. It was also taking over even from pre-PC activities, as 59 percent used it more than a book, 52 percent more than the radio, and 34 percent used it more than they watched TV.
