The Red Wedding finally arrived, and as a reader, I was not in the least bit disappointed. There were minor changes, but I believe the producers at HBO did the scene justice, and they even managed to throw in a little surprise, such as Talisa, Robb's wife, taking a knife to her pregnant belly four or five times. I have watched the episode three times now (I've been waiting for this event since I heard the announcement of the series), and the more I see it, the more I appreciate the setup.
Throughout the scene there's a slow buildup. Everything that is said or done escalates, starting with Catelyn talking to Roose Bolton; his expression when she said, "Ned didn't think it right to break a man's jaw on our wedding night," is something I didn't catch the first viewing, and it was priceless, because, as we all know, he planned to do worse. Then the doors were shut and the band in the balcony played, "Rains of Castemere." Even though I knew what was going to happen, I got a sick feeling in my stomach. I was nervous, thinking, "Here it comes." I haven't felt like that since the final scene in the Sopranos--I still cringe seeing Talisa's fate.
The outrage from viewers, the total shock, was unbelievable. It reflected what I felt when reading the books (I threw my copy across the room). Even my dad, who is usually immune to these types of events on television and movies, was amped about the Red Wedding, saying, "It was a slaughter." There are not many shows or stories these days able to surprise its fans, and only a few have the guts to do what Game of Thrones did last weekend. The writers and producers could have decided to let Robb or Catelyn live because they're fan favorites and drastically alter how it is in the books, but they stayed true to the source material.
I wouldn't be surprised if fans were still outraged. I had a friend on Facebook tell me the Red Wedding was why she stopped reading Martin's novels. As I told her, she shouldn't have given up. New tales and characters are coming--wait until you meet House Martell from Dorne--the paths of old characters will shift with this event, and as Varys said in the beginning of this season, "The revenge you seek will be yours in time."
Be patient, like our friend the Spider.
In the meanwhile, here's a couple videos of fan reactions and George R.R. Martin talking about why he wants his readers to be afraid.