Who do you think is the best POUND for POUND fighter in the UFC, and WHY?

To be honest I'm a huge fan of Jones but he is way to new. Anderson Silva is my choice. I would've said GSP but I really don't think he takes as many risks as Silva. Silva wins by taking more risks. He won't take the fight to the ground or anything but he KO'd one guy by using a technique he learned from Ong Bak. He KO'd Chris Leben when Leben had never been KO'd and hasn't been KO'd until Stann and even then I found out Leben was very ill and on top of that took the fight on very short notice. He KO'd Belfort with a front kick and nobody's been able to do that to him.