I had this discussion with my vet last week. He said that the legistration to regulate the chips is finally proceeding in a forward direction. He advised me to wait until the spring when it would be clearer what would be the standard.
I googled the keywords and found this article which makes sense as to why he told me to wait until the spring. Legislation was sent to the President for signature on November 3rd. It states that the group has 90 days to report back on how they will succeed in having a standard chip that will be readable nationwide and hopefully internationally. ISO is the way to go!
http://sev.prnewswire.com/health-car...3112005-1.html