Solid pilot. Lots of characters packed into an hour, so I can imagine people who haven't read the novels might feel lost. But then again most shows have ensemble casts, from Mad Men to Lost, and naturally it takes some time for characters to stand out. Ned, Catelyn, Jon, Tyrion and especially Arya stood out, whereas characters like Robb and Theon were just...there. I'm sure that will change.
The visuals were stunning as expected, not much that hasn't been said about them. Going in, I was more concerned with the writing and acting, and from what I saw both were good. Sean Bean is excellent as Ned Stark, and really held the episode together. Mark Addy was also very good as the king; Bean and Addy's scenes together were some of the best in the pilot, from the introduction to the crypt scene.
Seems like some folks have complained about the Targ/Dothraki scenes, but I thought they were good overall. Loved how they transitioned from Robert in the crypt lamenting the remaining Targs to the shot of Dany. The only thing I didn't like about her first scene was Viserys taking her clothes off; seemed kinda forced considering we get to see her nude later anyway. The wedding looked kinda off at times, especially the dumb fight with the guy's guts getting ripped out; I wish that scene was shot a bit darker, like with the sun going down and fires everywhere. Would have definitely cut down on any cheesy/corny factor. Still, Dany was perfect as was Viserys so I can't complain too much.
random stuff:
-really like the music
-the intro credits are VERY good
-the ugliest scene was that green screen shot of Bran climbing, yuck
-Arya had like two lines, yet stole every scene she was in. Perfect casting omg
-the ending was perfect. Reading reactions on twitter was hilarious, and I can't wait to hear more reactions from people who weren't familiar with the novel
-perhaps the only thing I really didn't like: a couple odd edits. Right after the beheading scene, the party is on a bridge with a dead stag blocking the path. Just seemed so abrupt, especially considering there are no commercial breaks. A similar thing happens after Drogo views Dany and rides off; the next scene shows Viserys, Dany, and Illyrio looking across the ocean