Chris Willman Music WriterDrake has been mostly tight-lipped about the details of his “Certified Love Boy” album, set to come out late tonight, but he’s heightening anticipation with a city-by-city billboard campaign that is alternately hinting at and outrightly revealing some of the the other artists being featured on the long-delayed release.Each of the messages refers to a featured guest from the city where the billboard has popped up. In Georgia, the reveal is none too mysterious.