I just read that Carla Bley's most recent long-form work, an oratorio for boy's choir and big band, La Leçon Française, has, perhaps, been performed again and, perhaps, FINALLY, been recorded. Until now this is the only part of it I'd heard. The performers are The Choral Academy of Dortmund and the Bohuslän Big Band with Carla Bley conducting and on piano and Steve Swallow on bass.
Here's a longer description of the piece and the plans to record it.
It's awful that one of our major composers has significant pieces that have gone unrecorded.