We couldn't shake the feeling that the mysterious Samsung-branded Windows Phone 7 Series device being passed around at MIX10 this week was just a warmed-over i8910 HD, and it turns out there's a very good reason for that: Samsung says it is a warmed-over i8910 HD. Even crazier, TechRadar writes that its contact at Samsung basically pegged the stunt entirely on Microsoft, simply saying "they used the i8910 HD to demo Windows 7" and that "this demo was a one-off." The whole t