According to a post in Cynopsis Digital:
Apple and AT&T pulled off the first live streamed event on the iPhone on Friday - a live concert in from UK techno band Underworld at the Fox Theatre in Oakland, CA. (Click on the "live broadcasts" link to listen to an archived video of the event.) The concert, which AT&T more or less kept under its hat to avoid traffic problems, utilized Apple's new HTTP streaming protocol using adaptive bitrates technology to deliver a steady broadcast under varying network conditions, per NewTeeVee. Akamai and Inlet Technologies helped power the event.