Yeah ... this episode really had highs and lows. It was Exposition City, for starters, and a lot of the exposition was kind of awkward or even inexplicable.
First, the Bad:
An entire scene of Viserys talking about dragon skulls? To what purpose? And throwing in dragon names from other fictional sources is pretty lame, even if Vermithrax did make me chuckle.
I've pretty much given up on the Dothraki "horde" looking like much more than a couple dozen guys on horseback. The actors are all doing a fine job over in that subplot, but it feels absurdly low-budget compared to the rest of the show.
Littlefinger giving the Hound's backstory to Sansa? Seriously? Probably the worst thing the series has done. Totally screws the Hound's character, and contradicts the point of the story -- nobody is supposed to know it except the people who were there, and Sansa, after the Hound tells her. It's kind of pivotal to the Hound's character. I suspect this means the Hound isn't going to be much of a character in this series, and that is a terrible mistake given his importance later on down the line.
Now the Good:
Catelyn's arrest of Tyrion. Calling out each of the men by their lord's names. Very dramatic and well shot. I continue to love Dinklage in this part. His manner as Tyrion is arrogant but not off-putting.
Julian Glover, as Grand Maester Pycelle, is hiding a lot behind the tired old man facade. He's a great actor, and I'm just disappointed he's too old to have been cast as Tywin Lannister, because he would have been incredible.
The "you don't know cold" scene in the dining hall at Castle Black when Thorne gives Jon and Sam a very sobering dressing-down was probably the best scene in this episode. Owen Teale (Thorne) is kicking the ass of a fairly minor part.