What Owen refers to as 'noise in the sky' looks to me to be more like posterisation.

Noise in the grey areas is much less significant, and if there was in fact noise in the image, it;s more likely show up in the grey areas.

but the two images displayed here show more noise in the blue channel.. ie. posterisation.

Very common to see in the blues, I get it quite often when I underexpose blue by too much(over use of grads and polariser combinations!!) at ISO100 on my D300, and have seen it with D700's/D3's too as other folk's examples of how common it is.

I'm not 100% sure as to why it happens so much.. actually it's the explanations of the phenomenon that are hard to understand!! Soemthing to do with exposure levels, signal to noise rations from the camera, and colour management too.

Anyhow.. enough grumbling from me.

What I'm curious about is the levels of distortion now!

I was only recently reading a new caption on DPR(yep! I still occasionally visit DPR, but only for some brief news/review/info value.. most certainly not ... their forums

Lots of drivellous rantings about how manufacturers are cheating with respect to lens design, because the cameras now have automagic distortion control built into the camera!

yeah!? .. so?
(with the caveat that it has to be user selectable!)

Oh! and on another note.

I was recently wandering aimlessly wandering about town, and noticed a Zuiko 7-14mm f/4 in a shop window(sorry can't remember how much!) .. but JEEZUZ!!.. that thing was HUUUUGE!!!
I reckon... quite possibly as big as the Nikon 14-24/2.8