Normally, I shy away from casting news as pretty uninteresting. Even casting news for GRRM's Game of Thrones, being serialised (probably) on HBO isn't super exciting for me. I question what exactly Alfie Allen is bringing to the table, and how he has managed to swing as role in something so epic and exciting as his first acting role (clue, starts with nep, rhymes with... oh wait, nepotism doesn't rhyme with anything).
Here's some excitement though. I fucking love Lena Headey, and the lesbian sex scenes later in the series are going to be horny as hell with her in it. Awesome.