Thats only part of the potential problem. If they (bitfinex/tether) were issuing tether without any backing ($670 million remember) and using margin on top of that to pump btc, We are in a lot bigger trouble. Not only will everyone who holds tether have a worthless token but we have no idea what any coin is actually worth in the real market.
Its been 24hours since bitfinex said they would be releasing an official statement.

I might be getting paranoid here but it feels like de ja vu (goxed)