I am really interested in the 35mm f/2 IS lens (I seriously doubt the 24-70mm is going to budge my 24-105L, 100L Macro, and/or Tamron 24-70mm f/2.8 VC). I have had a strange love for the 35mm f/2 on full frame anyway, despite it's limitations (and it certainly has them). Despite the eye-browing raising price of the new non-L IS primes, the reviews have been overwhelmingly favorable for them. I have held off on replacing my 35mm f/2 with a 35L until the reviews are in on this new lens.
If it as sharp as the other new primes wide open, improves the transition to OOF area, and has color rendering that somewhat rivals the 35L, it is going to be a hit even at that price. The IS is only a bonus. I really like the 35mm focal length on FF, and this lens looks to address all of the issues of the first generation lens - just at a price that is about $200 higher than what I would have liked it to be. I would expect the prices to drop by a $100 or so within six months, and I will probably snap it up then.
I would love to see them give this treatment to a 20mm prime that is sharp into the corners. I would gladly let my 17-40L go for something like that.