1. More DR actually can be useful for wedding shooters.I see very little evidence of that - most wedding photography has nothing to do with image quality per se, and more to do with dicking about with cross processing and other PP gimmicks that will work just fine regardless of the source of the Raws.
In fact, I'll very happily argue that bird photographers have far more need of great IQ than wedding photographers, and the 5D Mk III will make an excellent birding body, assuming enough focal length...
2. It can really be useful for landscape shootersA tiny subset of the potential customer base for the 5D Mk III. For everyone else, it's a bloody superlative bit of kit - the first FF camera I've ever been actively interested in, and yes, I'm a bird 'tog.
and the 5D3 IS also their top landscape cam so no I don't think they listened to the pros too well about it all or to the wrong set.Far more likely, the 5D Mk III isn't intended as a landscape camera.
This whole thing of DxO making such a big deal of the low ISO DR from the D800 to the extent that this characteristic alone has effectively raised it above all other DSLRs, is just another example of DxO bias: the weight they've given this one D800 metric - which it just happens to beat the 5D Mk III in - makes no sense whatsoever except in the context of "massaging" the final mark.
For many potential users, "amazing" base ISO DR is an irrelevance, and there are areas where the 5D Mk III's files are better than the D800's; and in most others, particularly once we're off base ISO, the files are essentially equal in terms of the end result.
Yet the D800 is the star simply because of its low ISO DR performance?
It's a bloody fix, pure and simple: give me excellent all-round file performance (and anyone who says that the 5D Mk III doesn't do that in spades, is a liar, an idiot, or both), stellar AF and high FPS any day.
Despite what DxO and the habitual whiners and axe-grinders on here have to say about it.