Hello, I have been using Bitcoins for some time even before they were popular. I have a background in writing secure code that should be a major help on this project, and I am also a member of multiple security organisations. I have reviewed the documentation for how to uses bit coins on a web site. What I would suggest is to have the ability to pay in with bit coins automated however the payouts should not be. You can charge a fee for paying out what this will do is prevent anyone even if your server gets fully computerized from stealing your wallet and taking your money. I Also suggest that we make the server decide a winner not the client computer as this would lead to problems. I can make you some slot machine games in html5. The hard work would be integrating the Bitcoin payment system. The real Bitcoin system not MTGox or any other. However,if you want MTGox I can do that to.