Canon loyalists saying resolution is bad?!? Heresy. The Canon party line is that more megapixels are good...or at least, that was the party line until Canon changed their strategy. Regardless, the fact is that more - or less - megapixels aren't inherently bad or good. Increased resolution has consequences, IMO mostly good, but some less so.
what is getting glossed over is that as resolutions rise, we are getting into the territory of diminishing returns. I think the DPReview review was very careful to clear about the lengths you need to go to in order to reap the full benefit of the resolution of the D800. for those who are making a living out of landscapes, that is not an issue, as they will have the lenses and tripods and understand the technique required to get it all to come together.
For those who are not prepared to invest in good glass, the resolution starts to become academic.
The argument about whether a 5D3 is better or a D800 is better is a little like arguing about whether a Range Rover is better than a Porsche 911. Granted, either will get you from A to B, but each has its own strengths and weaknesses which make it more appropriate for a particular task. Thus the 5D3 may well be a better wedding shooter's camera, while the D800 may be better for landscapes. Those in the market for a camera need to decide what their requirement is, and buy accordingly.
I am sure to take some flames for this, but for a broad section of the market, the differences between the 5D3 and the D800 are probably academic, and there will be no appreciable benefit going either way - provided you have some degree of skill, you will still take great photos.
For me, the decision is mainly driven by my wife's needs - for events, she really only starts shooting at ISO800. For large jobs that involve lots of images and little to no chance of large prints, SRAW is a must have. Realistically, given our investment in Canon glass, we are unlikely to buy a Nikon. For events, more fps is better. On a balance, the 5D3 will be the "easier" choice. There is no religion in it however. If you can't produce great images with either camera, then probably photography is not your thing.