I have a site that I stumbled and then I got a couple other people to stumble it but I didn't get even one visitor from stumbleupon. The tags were medium traffic phrases that do have people searching them on stumbleupon. I have stumbled several of my other sites before and with just the one stumble I got between 5 and 25 people but for dome reason they won't send anyone to this site. What do you think is the problem?