The Phantom of the Opera has been released as the first download available from Big Finish. The allows you to also buy two albums of music from the audio drama, and the CD version (released in March 2008) will feature interviews with the cast, singers and music composer.
A slightly-edited version will also be broadcast on BBC7 starting this Sunday at 6pm (not 6.30pm), repeated at midnight and available to Listen Again from here.
Here's a trailer:
My role in all this was the sound design and the final mixes of the episodes.