SingPlayer for iPhone back in May, we knew it would take a serious change of heart for AT&T to reverse course on the issue of 3G streaming. The app's super-conspicuous lack of 3G was one of the clearest statements around that the iPhone represented a level of data consumption that AT&T was fairly unprepared for, and that certain uses like VoIP over 3G and live video streams were just not going to fly. Well, we've just now gotten over that VoIP hump, and now AT&T has given in to SlingPlayer demand at last. AT&T says it has been testing an "optimized" version of the app on its 3G network since December, and Sling says the dynamic bandwidth adjustment should keep the app from bringing the network to grinding halt -- in not so many words. The 3G-friendly version will be a free upgrade to the $30 application, and should be available as soon as the revised software makes its way through the App Store approval process.