Like clockwork, the Apple (NSDQ: AAPL) iTunes subscription music service rumors are cropping up, again, and three Apple sites—MacRumors, MacDailyNews, and The Unofficial Apple Weblog—are reporting that it will be launched in September. The rumors all came from the same source, it seems, and details are: “$129.99 stand-alone or $179.99 with MobileMe, current MobileMe subscribers can add iTunes Unlimited for $99.99”. Such rumors have cropped every few months for the last three years, but generally speaking, everyone agrees that it is not a matter of if, but when Apple comes around and launches its unlimited price music service, subject to label and Apple agreeing on pricing and rev split…