Fierce deep-sea predator? Not so much:

"We are looking at something verging on the incredibly bizarre. As she got older she got shorter and broader and was reduced to a giant gelatinous blob, carrying many thousands of eggs," he says.

"Her shape was likely to have affected her behaviour and ability to hunt. I can't imagine her jetting herself around in the water at any great speed, and she was too gelatinous to have been a fighting machine.

"It's likely she was just blobbing around the seabed carrying her brood of eggs, living on dead fish, while her mate was off hunting."

http://www.schneier.com/blog/archives/2008/09/friday_squid_bl_138.html