They have invested to much into Robb as an on screen character unlike the books where his role was very minimal just to have him murdered at his own wedding. Season three may be the season where the TV adaption of the books change dramatically. No one knew or cared about robb when reading the books, on screen he is a major and well liked character, I highly doubt his death is going to come at the hands of a Frey in a cheesy wedding scene.
The HBO writers are going to fix one of the major book blunders by having Robb survive the red wedding and go out with a bang, hopefully he will kill the little brat king before meeting his maker. Anyone with a good sense of what makes a good TV series would know developing Robb as a character to simply kill him off as they would a nobody is going to suck for the TV show.
It may piss off many of the book groupies but it would make for a much better TV series.
Nice asshole @r8. You knew your post contained spoilers for those who didn't read the books. Why spoil someone else's fun? Fuck you.
The red wedding will be going ahead as planned. The creators and the author have stated that. I can't wait!!!