I gave it an "average." I was wary of being too excited about the return and gushing too much.
It was a very solid opener.
Dany's story is off to a strong start, and I was stupidly excited to see Selmy again. (I felt her story was too watered down and changed last year, but SoS has a lot of great Dany moments.)
Jon's story also suffered last year, but seeing Mance and Tormund in the opener gives me high hopes. I thought that Ghost being with the survivors of the Fist of the First Men was a bit of a head scratcher but...
Like another poster mentioned, I enjoyed the inclusion of the giant. I figured they would be a casualty of the budget, but was excited to see one on screen, even if they did not appear as I imagined.
I can only echo what was said above. The Tywin/Tyrion interaction was so spot on. (I loved the nod to what Tywin was writing.) Charles Dance and Peter Dinklage are dynamite together.
I like how they are cutting things while pulling some things in. For example, I thought the intro of Qyburn in that manner was an interesting choice.