Ser Seven is another terrific award winning actor. He will be going back to a place he's been before. This is a guy who once went to the wars with our Jaime, though it's a good thing that Jaime wasn't a kingslayer then, or all history might have been changed. And there are mountains in Westeros that he might know, though his character has never seen 'em.
More by week's end, maybe.
And the announcement? Don't ask me.