Wired Editor-in-Chief Chris Anderson recently tweeted that a T-Mobile manager “casually mentioned to [him] that they’re going to get the iPhone 3GS (but not 4, oddly) later this year,” and asked if this was common knowledge. As Business Insider points out, it is odd that Anderson would broadcast this rumor over Twitter instead of giving it to one of Wired’s reporters to research and report. Asymco has posted an analysis of…