onlinesource - 3:30 pm on Sep 19, 2013 (gmt 0)
-- Best guess after skimming through the long messages in this thread: the preceding bit you in the A** with Penguin 2.0 and any type of duplication [to be non-duplicate 85% or so unique is the last % I remember hearing] on the .co.uk domain probably didn't help, because duplicate content is duplicate content and I'm not sure who said it wasn't considered a duplicate on a separate domain, but they're incorrect.
I would like to get a straight answer to this. I plan on upgrading my shopping cart which will use this new system that allows me to control multiple storefronts under one admin. So this way, customers will see my .com and co.uk site but I have one admin to view orders, etc. The way the cart works is, you create categories and products and say, "O.K., co.uk can sell THIS product but not THAT product". Sometimes you have two carts selling the same product which to me means the same description, same price, etc. I don't see how this is not duplicate content but the cart developer assumes me it isn't.
I have noticed that both Amazon's UK site and Amazon's Canada site are hosted in Seattle, Washington... Most than likely they host all their domains on the same server and not in each country. Still, for instance the product "Grand Theft Auto V Limited Edition Guide" is on both the .com and .ca site and both use the same product description and the "frequently bought together" part matches too. The URL "/grand-Theft-Limited-Edition-Strategy/dp/0744014956" also matches for both domains. The product reviews are different, which could make it unique.
Again, I hear conflicting things on this. The cart says, "it's fine, don't worry". Others tell me to freak out! :)