I have been through their terms and conditions (not exactly a big read) and could not find anything regarding how the bitcoins are treated.

I deposited the bitcoins as bitcoins (straight from my wallet) - a set quantity and have not exchanged it into a dollar amount.

In the 'wallet' (profile page on the exchange), it shows a table showing quantity of bitcoins, and value of the bitcoins based on the current price.

I am waiting to hear back from them for an explanation and will keep you posted. But yes, I will not be depositing any more for the time being until I hear back from them.