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Karel, I'm referring to the broad array of severity I've seen across many, many devices. Some have no noticeable shadow. Some have too much. Most are in between.

I honestly thought what I meant was easily obvious...

I'm just messin' wid ya.
(but the shading is a still a tad irritating -- to me. I'll probably get used to it, especially as I'm going to use poor NokiLLO less and less)

My N800 has a slight uneven dark shadowing on the right side also I thought it was just me, I think it must be a design flaw in the device if we all notice it.

If you turn the device a little toward the left, does the shadow go away? Most likely. It's just slightly uneven backlighting. Calling it a design flaw is a bit harsh. Almost all LCD displays have it to some extent, except for those with ultra expensive, high color gamut LCD backlighting. I'm picky too, but in this form factor, price range and resolution, I doubt you'll find better.

jpj is correct as to the cause. It's just the manifestation that has varied so much (and I've seen just about every state I'm sure). Given that some LCDs exhibit virtually no noticeable shadowing, it's obviously possible to achieve that state in every single device shipped. It's just a matter of the LCD supplier establishing a more consistent quality process.

Mine has the same problem and it is extremely anoying. I still have the 770 and the screen is much better that the N800s. It does have a pattern (touch layer) that the N800 doesn't have, but the backligh is very regular.
On my N800 I have about 2cm that are much darker than the rest.
I am probably going to try to tak it back. I am usualy not very picky but it is very noticeable in mine.

Has anyone contacted Nokia to see if this is a warrantee fix? Problem in sending them in is they tend to send you back a refurb unit.

Well, I did with a unit just out of the shop. Shop refused to take it, Nokia told first that it is due to scratches on the screen, after I've put it to their attention that scratches are on the in-box protective film second answer was that it is due to mechanical damage to screen 'cause I e.g. have been sitting on it while in pocket. So not covered by warranty, offer to replace the screen for euro 170. Took it back in as is condition, have that nice answer in writing and final recommendation to come to state consumer protection agency and sue Nokia if I feel like it. Feeling pretty pissed off sincerely.