Stannis & Melisandre look good - about how I'd imagined them. Davos - one of my favorite characters - was too fleeting to make a judgment. Natalie Dormer is a bit old to be Margaery Tyrell, but she looks good anyways. (They upped the age for most of the young characters anyways, so I guess it's okay?) Renly looks a lot better with the crown on his head.
April is coming!
This link has some screen caps of the various scenes: Tumblr Of Thrones