I shot some comparison shots, to be the final part of my evaluation of my 16-35. I’m keeping it, and the 14-24 is up for sale.
I shot these shots all from the same spot, on the same tripod, using the same D700 body with the same settings (auto WB, Aperture Priority, 0 Exposure Compensation). All images received the same Lightroom sharpening settings of 35 sharpening, 15 detail, 90 masking. All comparison shots are 100% zoom comparisons produced as screenshots of Lightroom.
You can click the images for the full-size versions. Sorry for the long post, but I wanted to show what I’m seeing, which seems to be in stark contrast to what others think of the 16-35.
This is the overall scene that all the test shots are based on:

16-35 vs. 14-24 shot at 16mm f/4:
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16-35 vs. 14-24 shot at 16mm f/11:
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16-35 vs. 14-24 shot at 20mm f/4:
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16-35 vs. 14-24 shot at 20mm f/16:
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16-35 vs. 14-24 shot at 24mm f/4:
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16-35 vs. 24-70 shot at 24mm f/4:
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16-35 vs. 14-24 shot at 24mm f/11:
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16-35 vs. 24-70 shot at 24mm f/11:
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16-35 vs. 24-70 shot at 28mm f/4:
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16-35 vs.
24-70 shot at 28mm f/11:
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16-35 vs. 24-70 shot at 35mm f/4:
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16-35 vs. 24-70 shot at 35mm f/11:
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Conclusion:
The 16-35 has some light falloff in the corners when shooting wide open, but not much. The 16-35 is soft in the corners when shooting wide open, but not much. It does have some barrel distortion, more that either the 14-24 or 24-70.
The 16-35 is consistently as sharp if not sharper than both the 14-24 and 24-70 when shooting @ f/8, f/11, and f/16. In some cases, it is sharper in the corners @ f/4 than the 14-24, which is surprising because the 14-24 is stopped down by 1 f-stop and should have sharper corners than if it were wide open.
The 14-24 seems to consistently over-expose a bit, at least by comparison.
I shot a 17-35/2.8 for a bit. I found it to be in the same league as the 24-70 in image quality, weight, and cost. The 16-35 is cheaper and lighter than the 17-35 and image quality is at least as good, so I can’t see buying a 17-35 over a 16-35. If you’ve already got the 17-35, I don’t know if you’d have a reason to switch, unless you think you need VR (I don’t think you do).
In the real world, all are excellent, and no one should feel bad about choosing any of these excellent wide-angle zooms. For me, for landscape shooting, the 14-24 is the worst choice due to a lack of usable filters (there are exceptions, but not many). For other uses, such as night/concert/indoor shooting or architecture, the 14-24 might suit you better. Given the lower cost and weight of the 16-35, it seems to me Nikon has a new “holy trinity” of 16-35, 24-70, 70-200 v2.
P.S. A local pro, about 30 miles from me, also finds this lens to be awesome. Other reviews are whole-heartedly unimpressed by this lens. Could there be a sample variation problem? Tough to say. All I can say is you should seriously consider this lens before paying more for one of the 2.8 lenses.