On Tuesday, Microsoft Corp. ( MSFT , Financial) made a big surprise announcement: it plans to acquire troubled game developer Activision Blizzard Inc. ( ATVI , Financial) in an all-cash deal that values the company at $68.7 billion, representing a 35% premium to Monday's closing market cap of $50.9 billion. If everything goes according to plan, the acquisition is expected to close near the end of fiscal 2023.