Officially releasing her first single in quite some time, Katy Perry made a stop in New York City this morning to greet fans and interview with NYC's Z100 radio station in SoHo. Arriving in true Katy fashion, she appeared from her smoke-filled Gold-plated semi truck that's been traveling the country promoting her new album, Prism, debuting October 23. Katy's latest single off her new album, "Roar," hit the airwaves over the weekend and dropped on iTunes at midnight Monday. "Roar" is said to be one of the fastest selling singles of the season, and will break well into the Top 100 by Wednesday when the charts are renewed weekly. MTV's James Montgomery notes "Roar" to be a sort of ...