I am having the same question.
It seems like everyone gets the 8600 and no one talks about the D800. I am looking for a notebook to use for grad-school (papers, intensive excel work). And in my looking around I am leaning towards the D800 just because I've read that it is more of a business notebook and may be a bit more reliable (although maybe not cutting edge).
This is all just my opinion though as I don't have any experience with either model.
aside from the case, what's the difference?
latitude costs a lot more.

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