CNET:

With AT&T officially announcing its “Mobile Share” plans and joining Verizon Wireless, there will soon be two options for customers who want to get into a family plan for data services.While these plans aren’t the best deals for individuals, large families or even groups of really, really close friends may want to consider them. That’s because the more people who sign on, the lower the price per gigabyte and user. Of course, if someone is a heavy data user, that person may want to stick with an individual plan, or risk hogging up the total available data for everyone.By and large, the plans are fairly similar.