Just wanted to chime in - don't have any "answers" on all of this but did speak to a customs agent I know and he was not happy about it. He said he is trying to involve SCI and the NRA because all they are doing is targeting hunters with this process. He also said they plan to do away with the form 4457 which makes no sense as that is required by a lot of the foreign countries for their permits as well. He said you can drive across a border and take all the guns you want without any paperwork but not if you are flying. He said he has a meeting tomorrow on it and will touch base with me after it if he learns anything new. He did not have an implementation date as he said their software is not even ready to handle this.
@Wheels - regarding your mention of the agent entering your information, not sure about that when entering the country but I did question an agent once when we were obtaining our 4457's on new firearms and they run the S/N against the stolen firearm list and also run a background check to make you can legally own a firearm. The customs agent I know also verified that he does this and thus the reason other countries like to see the 4457 because they know that the owner and firearms have been checked out by the U.S. The information is
not supposed to be retained in their system!
Wish I had firm answers but it's kind of like dealing with the airlines - every agent you talk to has a different answer that may/may not be correct!
I'll update if I learn anything else but I have not had any clients travelling that have mentioned any issues thus far.