I hear rainbows are a good sign...like a smile...:-) I remember when I was going through my Teacher Initiation at a Mystery School up in Uttah, there were rainbows all over the sky right before the initiation.
So, I think rainbows at BM were a good sign too...yet another initiation took place...we'll see where it takes me ...:-)
This came from a friend of mine...made my jaw drop...
http://www.wolfsmithmedia.com/images/burningmanrainbow.jpg