Ever since Steve Jobs unveiled Apple’s impossibly hyped iPad, frequently maligned as the giant iPhone you never thought you wanted, observers have wondered whether it would catch on, and with who. Well, try most people with $500 to spare (the going rate in the U.S. for the lower rung WiFi-equipped machines). With the devices due to hit stores in the U.S. on April 3, Katy Huberty, an analyst at Morgan Stanley, projects Apple will sell some 10 million iPads by the end of December, doubling the estimates she made earlier this year.