man bitches love jaime or something, every women i've talked to today about game of thrones has been super upset about that scene and how it "dramatically alters the character of jaime". bitch, the dude threw a kid out a window how the fuck you gonna cheer for him... oh yeah, he's hot.
The thing about Jamie's character is, if you remove Cersei from the equation, he IS a good guy. Throwing Bran from the tower etc was due to Cersei saying, "He saw us, he'll tell someone". There are many instances where you can see that things bother him; listening to King Aerys rape Rhaella etc, and getting agitated and wondering if they shouldn't be protecting her. Killing the King to save the entire city. The dude went around with a title and a bad reputation that he willfully took on, because he knew the King's plans. A smaller point is that he is always kind to Tyrion despite the rest of his family hating and resenting him. The only time he was ever terrible was the whole Tysha thing.
The change messed up the entire tone of that scene, and will unduly serve to make him more of a monster to the audience. It isn't far after this event that Jamie begins to pull away of his own volition, now it will be in response to Cersei's attitude after this.
Also it creates the idea that Cersei is a victim; it tilted the tone and moral compass of several characters in one fell swoop. That's horrendous. The "external" crap was a whitewash of the event; (GRRM's explanation of the change) most smart people would have seen it as it was meant to be seen. A moment of comfort that became far more due to grief and the mutual loss of a child.
Now it's solely desecration of an altar, plus a moral sin layered upon incest, and a step back from the noble man Jamie has just recently realized he is not.
This will likely only go in one way; Cersei will obviously spurn him, and he will turn from her and work towards being all that a Commander of the Kingsguard should. Which ALSO taints that; Jamie stopped being concerned with glory, and became more concerned with being...well maybe not a good person, but one who stands for something more than broken oaths.
A man who killed a King he was sworn to protect, and did so saddling himself with a title of disdain, and a reputation of an oathbreaker, is not the same man who forces himself upon a woman who clearly does not want his attentions. There's also a lot that goes on in that scene that shows that Jamie also grieves, but for him it is muted as he was never given a chance to be a true father to Joff. Hell, a large part of that scene was called back later when Jamie mentions he'll give Cersei more sons.
It was an atrocity. I already saw what the change to Dany and Drogo's consummation ride did to people's assumptions of the Khal in season one; most tv viewers were convinced he was a barbarian, and Dany a whore who turned a rapist into a whipped husband. Instead of what readers saw, that the Khal was actually more intelligent and more gentle/considerate than any outsider gave him credit for. It was a specific thing that led Dany into becoming who she was, because here was safety.
Now, they'll change this, and no matter what Jamie does he is still an incestuous rapist. I have no idea, none whatsoever, how on earth this change was necessary to facilitate the dramatic change Jamie will undergo. Or rather, I have no idea how it will do so in such a way as to make the viewer understand how differently he views things, mostly due to Brienne's influence.
I understood other changes; Roz being a character meant that it was easier to get across to viewers that anything Littlefinger does, even in the guise of kindness, is usually only serving his own ends. Shae and Tyrion having a love story I think was to indicate that Tyrion is actually a good person; most of what we knew of Tyrion, especially in his marriage to Sansa, was said to himself. (That said, I dunno how they're going to get Shae to turn traitor and not have it seem even more outrageous than the book. The book showed her as more of an opportunist than the show does.)
This change however, really feels like it was more made to shock. The book wasn't rape; he was forceful, but not harsh and iirc did not even start undressing her till she responded to his kisses. The show was absolute rape; because Jamie had been in King's Landing many weeks prior to this event (Whereas in the book he returned just as it happened) we were able to watch Cersei shutting him down over and over again. When he went to kiss her, she turned away. When he asked her about the two of them, she said he was too late. So watching a scene where, given the background info on Cersei cutting him out, and then seeing her tell him no over and over again while he rips her dress, ick.
This quite fundamentally changes his character. Brienne is the catalyst for Jamie's change, because of how she views him (prior) and because of how she views honor. Jamie was a bit more good than given credit for, but he was also often a grey character, so with this act it's like he went slightly more dark before he's going to be redeemed. But I don't personally think it will work like that. He's always going to be a rapist now.
He is totally hot though, but the whole Brienne/Jamie thing was really very interesting, just for how Jamie views her. At the beginning he compares her to Cersei and keeps telling himself he doesn't give a shit what Brienne thinks, but by the end he's saved her life multiple times and he feels ashamed by some of the things she says to him. And she's not beautiful, not a queen, not anything Jamie has ever given a shit about, but for the first time he cares about something more than Cersei.
I don't know how they continue from here.