The bigger question is: Is Mintpal holding even more Coins, also Bitcoin in Hotwallets and not on cold storage?

This is for me, a reason, moving ALL my coins out of Mintpal. Thought this is a good exchange, but this showed me that they need much more security.

Sure, every exchange could be hacked, but it was Mintpal and not Poloniex/Bittrex/Cryptsy.

Think about it