Only a few misguided souls think that the IQ from a 35mm dslr is equal to or better than a MF back. It seems that those people haven't really used a back, relying instead on the internets.
The argument that has traction is that the latest generation of 35mm dslrs (D3x/1ds3/5D2) have FANTASTIC IQ, great color, are cheaper than the backs, are more usable, and more flexable. In an age when most images are destined for web, maybe a double truck on a crappy web press, large files aren't necessary. If you shoot people, the backs are actually too sharp.
I rent backs when I need them, which is less and less these days. (I am planning on renting a H4D ASAP.) For editorial work I shoot film because I want the that 4x5 or 6x7 look.
The above doesn't apply to landscapers or products or buildings shooters. You guys know what you need. If you shoot for money, and you shoot lifestyloe, well, its hard to argue for the extra IQ a back gives you over a D3x or a 1ds3, or a 5d2 even, when that extra is lost on a page or screen and costs at least $10k more than ds3/d3x/5d2. Add the simplicity of 35mm for fast breakdowns and set ups, less to go wrong, and a high return on the investment = 35mm dig is the better option. I'm not saying don't shoot MFDB, do what works for you, I'm just putting the argument in perspective. That being said, the H4D seems to go a long way in functionality and David Grover's 800 iso shot is impressive.
The one think Ken R. picked up on that sticks in my throat like a chicken bone is that the MF cameras all kind of suck, save for the H4 and the S2.* Aside from an S2 or an H4, the best solution is the battery hungry Contax (no longer manufactured) or the non "d" version of the RZ with a dead plate adapter from Leaf, or an old 500 series Blad. So if you don't like the H4 for whatever reason, the S2 is not really an option (silly price, track record of SLLOOWW repairs), you are left with the Mamiya DF or the antique and collectables from KEH: 6008 with a Sinar back, AFi (not manufactired, not widely available in rental), Contax.
This is just my opinion, not a holy war.
* Disclosure: I have not handled an S2 or an H4.
Honestly, I think that Ken has been exagerating putting the word "review". I think his article is more an overview than a proper review.
But there are some interesting points that surprised me.
The thing about Ken Rockwell is that everybody critize him (with some reasons) but everybody look in his site from time to time.
He has become a character. Is he trustable?
So far, there is no reactions war ff vs MFD to this article like the OP anticipated.
-O, nobody is interested in Ken's article or do not trust him,
-O, is it possible that Rockwell succeded in something that the MFD gurus here have been failing so far: convinced that MFD has better IQ than FF !??
Fred.