I decided to give this casino a try. I placed a bet, it won. I put funds for withdrawal and I have not been able to withdraw for more than a day. If anything changes I will report here.
As the above members have explained, according to their terms, a withdrawal request may take up to seven days, or even longer, to get processed. However, this is supposed to happen only if they doubt there is something suspicious about your account or gameplay and they need to investigate it.
Did you bet with yur own money (money you deposited) or with money you won from one of their contests/promotions?