You can lose your position on the leaderboard, though. There are still a few more days for people to pass you and then you would only win .1 BTC.
That's very true.
We do not even know whether or not your leaderboard position will prevail, let alone talk about the potential for social engineering back the sportsbet account, Sportsbet not crediting your account, and a whole range of other very valid concerns.
Just wondering, are you Arrogant on Just-Dice?
Because i'm pretty sure that you are trusted there. I don't think that some old JD user would have a problem trusting you with 100 or so clams.