The simple way to listen to Magic Broadcast is to use one of two players that pop-up in your web browser.

Magic Broadcast Player #1 - This connects to the higher quality stream, and there's less delay (so it's closer to real-time)... however, it's not as fancy and there's no volume control. When the window is open, it's playing. When you close the window, it stops.

Magic Broadcast Player #2 - This requires the Quicktime Plug-In for your browser. With this one you can stop and play, and adjust volume... but at the price of lagging behind the action.