Apple CEO Tim Cook may testify in the e-books antitrust lawsuit filed against Apple and book publishers by the United States Department of Justice, reports Bloomberg. The lawsuit was originally filed in April of 2012, and has focused on the so-called 'agency model' for pricing ebooks that Apple attempted to negotiate with a number of publishers. Apple had pushed for the agency model in an attempt to dilute Amazon's power in the book market, where it had offered vast discounts, even sometimes selling books at a loss, in order to attract customers who would make other purchases throu