I just went to Amazon.com and was STUNNED!
Amazon.com has shifted to the left. This is my homepage now:
And this is the image from an "About our Redesign" page they have (which I always recommend for sites undergoing such a radical change).
Wow .. Amazon.com has been like the LAST hold-out on tabbed browsing. I wonder how long the internal debate was about the switch. Also, I tried the amazon.ca site - still tabbed browsing, but their "about" page indicates that they are still in testing phase - so maybe it's an occasional thing? Or perhaps not rolled out to international sites yet.
In any case, pretty wild.