Follow the link - http://support.wdc.com/warranty/policy.asp It's showing 5 years for "USA, Canada and Latin America" as well. The only question is, what's accurate - that page, or the product-specific page?
Wow. Honestly, I would expect such a significant change to have an accompanying Marketing/PR blurb of some kind trumpeting the change (they live for things like that). Unless/Until there is some other official word I would err on the side of caution before automatically assuming it were gospel (especially with the lack of change on the product spec pages)