AjiNIMC - 3:56 am on Feb 15, 2012 (gmt 0)
Yeah, even I guess so. Different domain is supported in canonical URLs for sure but in href, they haven't mentioned it anywhere explicitly (not in examples not in words, everywhere they are mentioning URLs). Also they haven't mentioned any condition that it has to be from the same domain.
en-US, en-UK is a really cool way to put the content. I think I shall do the experiment with the assumption that it will work with multi domain.