They are upgrading back to the iPhone 3GS (http://www.apple.com/ios/ios6/) so that'd be the 3gs, 4, 4s, and 5 all on the same version. The 3GS came out before the Nexus One did, so imagine the N1 getting upgraded to JB. Doesn't the N1 have the same speed & ram as the NS anyway?
I don't know...