Actually, the time line is a little off - Grayson did first operate in Gotham, then he moved to New York and worked with the Titans and changed superhero personas (Where he established a long-term monogamous relationship with Starfire), then he moved to Bludhaven where he started his solo career (and must've started his Viagra regimen), as shortly thereafter he began a four issue bedding of the Huntress which seems to have been forgotten. Also, he married a socialite named Miggy. It was during his time in Bludhaven that Grayson also began his realtionship with Barbara Gordon and is now, I believe seeing some white bread librarian named Deb. (8 issues so far!)
Unless you read and believe Nightwing Annual 2. LOL. Then you'll believe anything anybody tells you.