Edit: English spoiler
It's out in Spain. (Google translate here).
I like the look of this chapter pack a lot. It looks like there are some powerful cards, but not even evaluating it from that perspective, I like that the variety of themes that are supported in this set and the way they have skewed the pack towards one theme (so that a Dothraki deck might be possible soon rather than after all six chapter packs come out).
The Raven attachment control is nice -- one of the few cards that cares about the Learned crest, plus it's searchable with A Time for Ravens.
Bastard of Bolton -- pretty good with MwnK : )
The Greyjoy event seems like it could lead to some cool plays -- you can use it to play the effects of your opponents locations as well (if I am interpreting it correctly) which should be a nice surprise.
Edric Dayne -- always nice to get more Nobles.
I like the witch that does not allow saves during military challenges -- I don't know if it's competitive but when I first started playing I found the self-savers really annoying to play against.
Then there's the whole Beric, Neutral Faction, Brotherhood element. I think I need to see more of what you can do with no power on your house before deciding if I like the theme.