I don't think it is regional. I checked the "Planet Earth" video mentioned earlier via VPN to these countries: Canada, Mexico, Brazil, Colombia, UK, Netherlands, Switzerland, Germany, France, Iceland, Norway, Denmark, Italy, Spain, Portugal, Bosnia & Herzegovina, Greece, Russia, Hungary, Bulgaria, India, Hong Kong, Singapore, Japan, Malaysia, Thailand, Indonesia, South Korea, Australia, New Zealand & Mongolia. I got to select 1080p option for all of them. It is also not tied to your Google/YouTube account. It doesn't look like location services matters. It is something else.