I'm really hoping Carrie sees this and replies. I think this is something that needs to be assessed by a certified behaviorist. These aggressive actions that the pup is showing alarm me.

It is pretty hard to really judge in cyberspace since the dog's body posture is unknown, so I'm not really sure if it is inappropriate play and lack of bite inhabition or actual aggressiveness. Remember dominance and aggression are two different things.

One thing worries me - do you have any children? or planning on having any in the future? The potential for disaster kind of screams out to me.

I have to agree with everyone here that the dog needs to be evaluated by a certified animal behaviorist. I would look for a behaviorist that also has dog training experience. Remember, not all trainers have experience in dog behavior. I am a dog trainer and I am currently taking classes in animal behavior, but I would never tackle a case like this - I don't have the credentials or the experience. I would refer it to one of the two behaviorists in my area or the Cornell University Animal Behavior Clinic.

In the meantime, I would put him on the "Nothing in life is Free" program. The Dumb Animal League has it outlined
here