I finally broke down and created a “Mergers & Acquisitions” category, which if things continue will easily be one of the bigger categories on this blog. In a deal valued at over $1 billion, John Wiley & Sons has entered into a definitive agreement to acquire the outstanding shares of Blackwell Publishing (Holdings), Ltd. (Blackwell, Ltd., the library book vendor and retailer, remains a separate entity and is not part of the acquisition.) The two companies’ 2005 revenues combined were roughly $750 million. Rene Olivieri, CEO of Blackwell Publishing and Wiley’s Steve Smith, senior vice president of international development and …