I signed up and then applied the bonus code without even making any deposits, I received the $10. I played around with different slot games. The wagering requirement is 50x so you really have to be too lucky to turn that bonus in a very big amount and be able to withdraw after making a total wager of about $500.
Chances for that happening are very low, and they have to be very lucky 
I think they are just giving out this $10 for testing all the games and see how casino is working, but I would like to see if someone from bitcointalk forum manages to win big and withdraw his reward.