Cats can be more dangerous then dogs. Yes, some dogs are scary and can be dangerous when biting people. However, cat bites can be extremely painful and can lead to infection. Cat teeth are more likely to break the skin, potentially infecting humans more so than a dog bite. Feral cats can be especially dangerous.
Cats are not more dangerous than dogs. This is a very general statement, but if one is comparing the two animals and their bites, it is a fair judgment. One way to look at this is that overall dogs have a greater numbers of large breeds and a large cat would never be larger than a dog. Second, dogs are more aggressive where as a cat may be protective but is less outgoing with it.
Statistically, there are many more problems with dog bites than there are from cat bites. It is hard to die from a cat bite. A cat might nip a little bit, but it's hard for a cat to cause lasting, serious damage. Dogs on the other hand, are more unpredictable. They can cause big problems.
I do not believe cats are more dangerous than dogs, but I also believe that not all dogs are really dangerous. A cat could potentially be more dangerous if it is a cat that is prone to scratching and biting and does not have it's proper vaccines. Overall though, dogs are less predictable and therefore I am more weary of dogs than cats.