My point exactly, the problem with you starting a separate thread about the new site, is yours will have much less activity, page views and will fall off the first page sooner.
I believe that anyone, US, Canadian or whatever that is having issues with the new site , would look first to the big post about the new site. That post is already over three pages and likely to continue to get bumped and stay on page one for quite some time. This one will fall off and fade away, being see with much less 'views'.
Why separate yourself because your Canadian, it's still an issue with the new site and much more likely to be noticed when together. What if the AMEX issue is not Canadian and others are having it and thought it was just them or their card, they are much less likely to have viewed this thread. Regardless if you want to keep this one or not, the information your provided still belongs in the main thread.
Just my $.02