Canon often do this kind of thing so that their products are fully tested by trusted professionals and they get the feed back their development engineers need. If they don't do this 1D4 fiascos are likely to occurr. While this kind of leak plays to our emotions, it is necessary for the developement of better camera models. But it is also kind of cool, becuase we get to hear very loose by telling information about prototypes which are currently in devleopment. We know (via other rumours) that Canon have a sensor patent / design which uses a different arrangement of the traditional bayer RGB array. It's likely that this new sensor is a test bed for that particular patent / technology and it appears to be an improvement over the current tech.
Bare in mind that the 5DIII resolves nearly as much detail as the D800. It's only the top end optical resolution of a few of the worlds sharpest lenses which can allow the D800 to out resolve the 5DIII and even then, there isn't much between them. Amusingly, Canon have more lenses in that bracket, than Nikon currently do...Canon's new 24-70IIL is the sharpest zoom lens so far from any brand. When Canon finally releases a camera body with this kind of MP count, there will be a lot of lenses to match the sensor's capabilies, where as Nikon have very few lenses which can match their current sensor tech. Most of their lenses do not optically resolve much over 22mp.
I think this new camera's sensor point to a more efficient use of the RGB array and probably the removal of the AA filter to create sharper and clearer details with the same resolution of 22mp. If this is the case, the new camera could easily match the D800's sharpness and detail but at a more effficient 22mp. the improvement in colour rendition sound good and i only hope that Canon have employed a simular supporting sensor design to achieve the same (if not better) shadow noise pushability in their raw files. This isn't an expanded DR as some have claimed, it's purely a better control of iso noise in the shadow areas of a raw file. Where as Canon files tend to break up and display banding with the same level of pushing in the shadows.
one could argue that the scene was incorrectly exposed in the first place...but the fact remains, Nikon / Sony currently have a 1.5 stop advantage in this single feature on their sensors. All the other features are a lot closer than the marketing / spin doctors would let you belive.