Workers have begun a 48-hour walkout, the first in 50 years for the outlet, over a proposal to sell The Observer to Tortoise Media, a digital media start-up. News and News Media, Mergers, Acquisitions and Divestitures, Strikes, Guardian (British Newspaper), Observer, The (British Newspaper), Tortoise Media, Barzun, Matthew W, Rusbridger, Alan Workers have begun a 48-hour walkout, the first in 50 years for the outlet, over a proposal to sell The Observer to Tortoise Media, a digital media start-up. NYT > Business