I would disagree.
I would suspect that there are many people sitting on the fence for a 5DII purchase, waiting for the 5DIII.
If/when the 5DIII comes out, one would assume that there needs to be enough differentiation between the two models to push people to buy the III. People are still buying the 5DI.
If the III is plenty more $$$ than the II, then there needs to be a reason why.
For those that own the II, there needs to be a reason to buy the latest one, unless money isn't part of the decision making process.
Even if the 5DIII is given the 7D AF system, there is still the 1.6 crop thing. I can take pictures with a 7D + 200mm, but I would need at least 320mm with the 5DII. Others have said it before, the 7D is like a really nice teleconverter. Wide angle shots do not look "right" to me on the 7D, so there is the "need" for a full frame. Selling both and replacing both with a single FF body doesn't really work the same. I use my 5DII much more than the 7D, but I see no need to sell it right now (big hit on the used market).
Buying one of those $10k lenses isn't an option for me, either.
So, unless the 5DIII is a game changer, I'm keeping what I have until the next product cycle. I suspect I am not alone. I hope that someone at Canon feels the same.
My 20+ year old film camera works just fine. As a hobbyist, I can't justify $2 to $3k every few years unless there is a *really* big improvement in the product or my wallet.
Will it? Playing devil's advocate here - I woner what percentage of 5DII sales came from 5D upgraders? Probably high at first, but sales of the 5DII have been strong since its release. I would think the 5D owners who were chomping at the bit (similar to many 5DII owners here) got their orders in fairly quickly, given the limited initial supply. At this point, how many people who don't own a 5DII are just waiting around for the newest 'affordable' FF camera rather than buying one that was released in 2008? Even if it's only a little better, they'd likely buy it. Plus, many people seem to still be buying the 5DII! In other words, there may not be a tremendous desire/need on the part of Canon to make the 5DIII a game changer.