Firstly, I am *ecstatic* about Natalie Dormer's casting as Margaery Tyrell. She was utterly amazing as Anne Boleyn in "The Tudors," capturing the unfortunate queen's unrelenting ambition and cunning with the juxtaposition of her vulnerability and humanity. She's absolute perfect. I'm in full agreement with Lady and xLordSnowx that the scenes between Cersei and Margaery with this powerhouse casting are going to be phenomenal.
I can't wait to see how the rest of the casting comes along!
I don't think it's going to be so much of the story going off-track as much as a rearrangement of things in order to make sure the series doesn't get stagnant.
You can stay engrossed in a book during a lull in pace because it still stimulates your brain. As film is visual and leaves a lot less to the imagination, a sudden stagnation in pace can be acute, causing views to lose interest much more quickly. By reordering some of the events to keep pacing in the show on an even keel, it will keep those who have not yet read the books engaged and interested. (Example Lord of the Rings: In the books Frodo and Sam encounter Shelob in the second half of "The Two Towers," but the film version puts it halfway through "Return of the King" in order to build up anticipation and thus make it more climatic.)
As to the gratuitous sex, you raise an excellent point that there is far too much "important stuff" going on in CoK and SoS to leave any room for needless smut, but alas, it is HBO, so I think we'll still get plenty of eye-fulls. (I wonder if it's in the contract or something, like an HBO requirement. "You will only get your show produced and run on this network if you meet the mandatory x% of smut per episode.") But still, we can dare to dream.
And additional thanks to TK for the link.
