Man, there is some serious despair in this thread. I took the Red Wedding about as well as some of you are taking the brain bashing. It was gory & über disturbing, but I've been thinking about it (kind of hard not to, as awful as it was), and man, Oberyn was just asking for it. He was so incredibly cocky. The writers went to great length to set it up that way. He was almost acting like a James Bond villain in that he was doing just about everything he could to make a spectacle out of it that he failed to actually kill the guy. Granted, he had a pretty serious beef and he wanted a confession in order to get justice, but it wasn't until he stopped to practically gloat that the Mountain seized an advantage and, well, you know.
However, FWIW, I do not believe Tyrion's time is at an end. I haven't read the books, but I think he'll get out of this somehow. Remember, the penultimate episode each season is usually the one with the major shocker. As David & D.B. promised, they have now delivered several big shockers, so who knows what's in store for S04E09.
Personally, I think they've been setting up some sort of serious Lannister catastrophe. The Lannisters are out of money (or at least not mining any new gold), both they and the Crown are in deep to the Iron Bank, and Stannis is gaining some traction on that front. Beyond that...I don't know, maybe it's just a feeling. But they've been winning a lot and for a really long time. It seems like something must be coming their way. Losing Joffrey was a blow, but not a really big one, in the end. Losing Tyrion would not really strike a big blow to the family, so I don't think that's it. It's high time someone really significant betrayed them, so that's what I'm thinking will happen next week. Possibly in S04E10, but more likely the next episode.
Dany's probably about to suffer some kind of setback as well. She's been too successful for too long without really losing anything of significance. I think losing Jorah is only the beginning for her.
But there are still tons of reasons to be hopeful, both for the Starks and for those who are anti-Lannister. I even think Stannis may finally be nearing the end of his infatuation with the Red Woman. He's been getting too much grief from everyone about it, most recently from the Iron Bank. I think once Melisandre threatens his daughter, it will be over for her.
Plus, Bran may be nearing a significant discovery. I'm imagining him leading an army of animals or some other creatures South to attack Rayder's army or the Others from the rear, while the Watch and the combined armies of Westeros attack from the Wall. It's a little far-fetched, but time will tell.
Arya may finally be getting out of those clothes sometime soon, so that will be nice. (As a side note, I think we may witness a showdown between Brienne and the Hound before the season is out.)
Sansa is finally starting to recover from all her losses and come into her own.
Jon is going to go places, I can tell they're ramping his story line up for something.
And then the whole thing will come crashing down in some kind of awful blood bath. But there will be some victories along the way.