Remember they made all the characters three years older so she's actually supposed to be sixteen I think...
Oh yeah, I LIKED IT. Yes it helps having read the book. But given how complex it is, how many characters there are and how detailed the backstory is, I think they did a pretty good job giving as much explanation as they could without it feeling too unnatural. And it IS just the first episode, you're never going to know who all the charactesr are or quite what's going on in the first episode of any tv show this complex. I've watched V for two seasons and I still call the main character "Juliet" because I keep forgetting her name (okay, it's Eric, but it took a while.) And that's V!! So I can understand why it will take a few episodes for non-book readers to understand everything.
I think the second episode will be a lot better too once things get moving and the character's starting heading where they're going. And of course having read the book I know there's good things coming...
I thought all the acting was pretty good (wooden, Loktar, really?) Sean Bean is cool and I think Jon Snow is going to be popular. The little boy playing Bran was good and Arya and Sansa seem perfect. I liked Tyrion's whore party but the best is yet to come from him. Mark Addy was good as Robert (I remember people complaining when he was cast.)
I actually thought Viserys was the standout character this episode. He was the perfect mix of creepy, scary, arrogant, petulant and crazy.
The direwolves were cute.
Good nudity from Dany (but appropriate to the story!) I think Lena Headey was pregnant when they filmed the pilot so that explains why the incest cliffhanger was a bit tame.
KEEP WATCHING IF YOU HAVE DOUBTS.
There's a viewer's guide (without spoilers) on the HBO site which might help new viewers
HBO: Game of Thrones: Viewer's Guide
And an episode commentary type thing
HBO
