There was a time, many eons ago, when Front Row was first unleashed to the world and touted as the ultimate in home entertainment solutions. So when Front Row 2.0 (and even the latest update, 2.1.3) was introduced with Leopard, there was a flurry of angry, angry Mac users who cried foul: Front Row's ability to stream audio was taken away completely. Is there another update in the works? Can't say. But we can tell you that there's a solution for all of you frustrated folks: Airfoil 3.1 from Rogue Amoeba.
Airfoil works around some restrictions that were previously on AirTunes, ie. Airfoil will let you send any audio--Quicktime, DVD, web browser, you name it--to multiple Airport Express units and keep the audio in sync between them, versus AirTunes' iTunes-only law. The latest release also allows you send audio from any source to an AppleTV...with some improvements.
For one, you can send any audio from your Mac to another computer (Mac or PC) on your local network thanks to their companion program Airfoil Speakers which is bundled with the download. And secondly: You can watch videos on the built-in Airfoil Video Player. Earlier releases of Airfoil had some audio-video sync problems when watching movies or shows via Airport Express--using the video player solves this issue. If you do use this feature, bear in mind you must have an output device enabled for it to work AND the video scrubbing and scanning isn't as smooth due to the video playback delay.
Airfoil 3.1 is $25, or $10 for the upgrade. You can download it at Rogue Amoeba here.