The Serpent Twins were created by Jon Sarriugarte and Kyrsten Mate of Form & Reform --
Here's their explanation of the twins:
These twin sculptures are the embodiment of the Serpent mythology that exists in numerous cultures throughout the world. The first is Jormungand, a dark harbinger of doom that Thor fights to save the human race in Nordic myths. His body comprised of blackened steel, he shoots fire from his mouth to prove his dominance over mortals. His twin, the bright Julunggul, shines in the sun and lights the night from within its 50′ body. She serves man by swallowing boys and spitting them out as men. They should both be fantastical in the old fashioned sense of the word!
MY NOTE: it seems that remotely operated helicopters are going to be the new annoyance on the playa.