Documentation from the 11:11:11 UpStage Festival is compiled here; a show-reel featuring excerpts from all the performances has been made, view it on vimeo
below are some images and recordings.
Osprey Therian links to the first bits of documentation from the Second Life Node:
Exchange Radical Moments: announcement of the UpStage festival at 9m in this recording of a live broadcast: https://bambuser.com/v/2115876
Images from the 11:11:11 UpStage Festival (click on the thumbnail to see the full size image):