Another Mystery - This Time, From the Ocean

What in the world is this strange beast, caught swimming by an oil-rig camera?

A gigantic transparent manta ray?

 A Really Really Big jellyfish?

 A giant chiffon handkerchief with LED lights? (Sorry, I couldn't resist.)

You can see it via LiveLeak, if you prefer.

Was this a bigfin squid? (No samples have ever been taken, though they've been observed -- and filmed -- in the wild.)

Weird...