The announcement comes at a time when there has been much speculation about MGM Springfield’s future in light of a Wall Street Journal story that reported MGM is in talks to purchase the Wynn Boston harbor casino being built in Everett. The significance is it marks the first time the casino giant has spoken of a firm date – in the past the opening date had been designated as in the fall or September – and it is earlier than any previous indications. SPRINGFIELD – In a surprise move, MGM Springfield announced through a press release on the morning of April 26 the casino will open on Aug.