Philadelphia Media Network, the company that owns the Daily News, Inquirer and Philly.com, announced that it would sell discounted tablet computers. To get the tablets at that low price, buyers must sign up for a two-year, $10-a-month subscription for digital editions of the papers. "I think it's exciting, in the sense that they're trying something," said Andrew Mendelson, the chairman of Temple's Department of Journalism. "But is the device enough?