Well, as a fan, I can say that the first episode was just about as good as anything I could've come up with - it's impossible to judge the overall quality on one single episode, though, and no doubt there will be stuff that I wish they would've kept, or not kept, or whatnot.
I'll talk to my mom about it tomorrow, probably, and see if she "got" it - she's kind of my gauge for people who haven't read the books, lol. It's easy enough for me to say I don't think I would've been too confused by who was who, but I've been reading the books for years, I know all the characters like I do my own family (better, in some ways...), so I'm not a good judge.
But we'll see!
I was afraid that the sex would feel gratuitous, or even (especially in the case of Dany) a little exploitative, but so far it hasn't been. The scene with Tyrion, Jaime and the whores was... actually relevant to the characters - if there's one thing we don't really see much of in the first book, it's the relationship between Jaime and Tyrion, I liked that they put that in there to show who these men are.
And as for Dany and Drogo, well... that was tough to watch. Which was perfect. It's not supposed to be a pleasant scene, and I'm glad they didn't sugarcoat it. I do wonder how it'll fit into Dany's overall arc in the season.
What else... I was impressed by how much they kept in, while doing a pretty decent job of outlining who the characters are and their personalities - they even kept in the bit about Lyanna Stark! Woo!
The performances all look pretty solid so far, though I'm not quite sure what they're doing with Viserys... in the book he's pretty goddamn vicious, and so far he's been kind of... pleasantly vicious. Maybe we will see the "dragon waking" in upcoming eps.
And the end - wow, how perfect was that? I've known that's how the pilot would end for weeks, but they did it damn well. Nikolaj Coster-Waldau hit that nail right on the head.
*taps chin*
I might have more to say after I've seen it again (and talked to my mom about what she thought), but I think I'm done blabbing for now.