Just about a year ago today, Penguin and Random House merged to create the world's largest book publisher. And HarperCollins(s NWS) announced in May that it's acquiring Harlequin. Now the season of consolidation continues: The large independent publisher Perseus is being sold off in an unusual three-way deal, Publishers Lunch reported Tuesday, with Hachette Book Group acquiring Perseus Book Group's publishing imprints and Ingram taking its distribution business. PL notes that the acquisition will bring Hachette's annual revenues to around $700 million.