Yes, we've seen Samsung's Galaxy Mega 6.3 at the FCC before. With its second visit, however, there's something special. The extra-large phone is back as the SGH-i527, and it's carrying AT&T-native LTE that hints at a probable US carrier deal. There aren't any other visible changes in the filing, although we weren't expecting any. The real question is when this behemoth will ship to the States, assuming it ships at all -- for now, any possible AT&T launch remains shrouded in mystery.