We won't be hearing from John Mayer for awhile. In a post on his tumblr blog, the singer announced: "Silent for the next few months, no singing for probably six, but all signs point to this being the last step in getting to perform again." Mayer canceled a tour in March because he had a vocal-cord growth. He had surgery last week, following an earlier surgery in October, USA Today reports. "If you see me out and about and I don't answer you when you say hello, I'm not ignoring you. Promise," he wrote.