I've bet few times and won a couple of times too. They seem to be paying out and I'm pretty sure the odds are in your favor, depending on how much BTC you have.
Have a look www.bitvsbet.com
Every day you can bet on 2 different things by sending your BTC to a specified betting address. So you become group A or group B. If at the end of the round (each day) your group bet the most money, you win a portion of the money of the loosing group. According to how much you put in of course.
There's a transaction fee, so be careful with that though. If you win and don't bet much, you might get less than you put in if you don't pay attention to the fee, since it gets subtracted from your winnings. Still, it's not really a big deal if you bet a "sane" amount of BTC.
nice scam