The tablet market may still be very young, but some tablet users are already reporting heavier usage than on their computers or televisions. According to the March 2011 survey from the now-Google-owned mobile ad firm AdMob, hours spent on a tablet are beginning to displace hours spent on other popular electronics, and tablets are increasingly being used to read books, shop online, send e-mail, and play games.

AdMob surveyed 1,430 US-based tablet users during the month of March and discovered that a whopping 77 percent said their desktop or laptop usage decreased after getting a tablet. That may be technically true for many users—I definitely use my computers less at night and on the weekends now that the iPad is around—but 43 percent also said that they use their tablets for more hours of the day than their computers. One third said they spend more time on their tablets than watching TV.

How is this possible when today's tablets are still catching up to "real" computers in some areas of productivity? A hint lies in some of AdMob's other statistics: more than two-thirds (68 percent) reported using their tablets for a minimum of one hour per day, and 82 percent said they primarily use it at home. If you assume the majority of those surveyed are not huge at-home computer users, then the numbers begin to make more sense.

In fact, 59 percent said they spend more time on their tablets than they do reading paper books, but 46 percent said they use their tablets to read e-books. That isn't surprising, and neither is the fact that 84 percent of tablet users use the devices to play games. (Another 78 percent use it to search for information and 74 percent use it for e-mail.) Content creation wasn't on the list of tablet uses, but perhaps it falls into the 19 percent who indicated they use their tablets for "other" purposes.

Still, although the majority of respondents undoubtedly still use their laptops or desktops to get work done, 28 percent indicated that their tablets were now their primary computing devices. That's a pretty hefty slice of the computer pie, but it's important to note that most people who currently own tablets are either early adopters or experimental newbies who might be trying to avoid home computer use in the first place. We may see the trends change again in a year when even more mainstream users get on board, thanks to the success of the iPad and growth of Android and RIM-powered tablets.