According to Alexa’s information, your unique visitors are around 30 per day. That’s a guess based on your traffic rank of 430,915. If you are relying on PPC for much of your traffic, that would explain it. PPC for gambling is 90% fake traffic, but AWStats would pick it up as real traffic. This would also explain the large number of people staying on your site for 0 seconds. Like KWBlue said, that stat does require a user to click to another page to register more than 0 seconds, so there is the chance that your site isn’t compelling enough for someone to want to click around (I haven’t really looked at your site, so I don’t know).
To your original question, you most likely are in the sandbox with Google as it seems to take a minimum of 1 year and probably closer to 2 years to rank for gambling related terms. You also don’t have enough backlinks to pull yourself up in the rankings anyway, with 164 being reported by Yahoo. For comparison, we don’t rank on Google either, with a 19 month old site, PR5 and 11,503 backlinks.
My point is that it takes a lot of time and hard work for new sites to get past the sandbox period. We are showing signs of crawling out, but haven’t arrived yet.