Back in late May, Apple announced that it would once again be holding its annual iTunes Festival in September, a monthlong series of free concerts at The Roundhouse in London. Just as it did last year, Apple has added a new channel to the Apple TV to offer live streaming and limited time on-demand replays of the concert series. The concert series kicks off on September 1 with Lady Gaga and includes a number of popular artists including The Lumineers, Queens of the Stone Age, Kings of Leon, Elton John, Vampire Weekend