Well, it's been a while since Nikon's 35+ megapixel cameras were released (with their oil problems etc) and the response from Canon's 50+ megapixel monsters, but having a previous experience with the problems that can occur when handling light with such beasts, I cannot keep myself silent and happy with these technological achievements. First of all, lets keep things simple by trying to figure out the problems of previous models of both brands in order to try and find some kind of solution to the most serious ones.
Let's see Nikon with their D8x0 models, the most expensive and promising technological beasts even today, equipment that most Nikon photographers either own or want to have just to witness first hand the detail of 36 megapixel per frame. We all know about the advantages, 36 megapixel of detail, crisp images with selected good lens and color rendition that is amazing because of the exceptional dynamic range of the SONY sensor. You got the idea? Nikon cameras with Sony sensors are a giant step towards better camera systems. This is what other competitors should do in order to improve the quality and not just produce quantities of cameras.
Nikon seems to understand that you cannot develop the best camera body without the best camera sensor and sony produces the best camera sensors out there hands down in terms of detail, white balance recognition (whites are whites, not yellowish, greenish, blueish) and minimal noise creation. Of course they cannot fit everything in one sensor (yet), let's not forget marketing! What was wrong with these D8x0 models? At first it was oil coming on the sensor (spare me the details, Nikon should have tested the housing prior to releasing it). Some say the problem is gone with D810 models and that the previous D800 models were "successfully repaired", meaning "patched".
Tell me how do you "patch" a 3.500 euro camera with some duct tape inside the housing and get away with it? Ask Nikon service, they know! How do you "patch" the conscience of the professional who suffered reputation damage from your expensive piece of crap? You can't! And how can you explain to the customers that their photos were ruined because of Nikon's bad hardware and why do they need to care about this, if they paid the photographer and not Nikon? And this is just the beginning of an endless argument.
The same goes with Canon's hardware. It's not the oil this time, but reports about autofocus problems and image grain. I would not like to comment on that rumors as I have never even seen a "5DS?" from close range. I can comment on Canon 6D firmware problems that make me believe that Canon just doesn't prepare the cameras for photographers, but they want them out of production as soon as possible never to repair any firmware fault again (despite some small updates even now and then).
To be more specific, the introduction of GPS in Canon FF cameras was a great addition. In fact, it was so great that I used it a lot, but from the first day I found out a big problem that it is not solved even today after 2 years of ownership by any official firmware update. The GPS did not automatically turn off when the camera was shut off! When you turned the GPS on, it stayed on until you manually turned it off from inside the menus. If the camera was just turned off via inactivity or you switched it off via the button, the GPS stayed on and drained the battery until next use. I mean WTF? 2 years later the issue remains the same and only via contribution of a tampered 6D firmware was I able to automatically turn the GPS off when camera was turned off. Implementation from the Tragic Lantern guys took 2-3 days and I had the updated firmware running in no time, but come on, this is what we prefer Canon for!
In conclusion (I have told it before and I keep supporting this opinion) Nikon creates good camera bodies with lenses you can use conveniently for both crop and FF bodies, Sony creates the best camera sensors with faithful White Balance recognition and minimal image noise, Zeiss creates exceptional camera lenses, almost out of this world (along with their prices), Pentax has great firmware ideas for increasing dynamic range and Canon is the most "hackable" camera in terms of idea development as Magic Lantern (Tragic Lantern, too) can add focus peaking, zebra patterns, manual shutter expansion to as long as you need per frame and way below the 30 second limit. You can also take DUAL-ISO images meaning a result of 1 image with expanded dynamic range in half the native resolution, time lapse without other hardware, noise suppression for Video, automatic restart of clips after reaching the hardcoded limits, focus stacking automation and so many other that I am forgetting right now.
So who do you want to pay for your new camera next time? I know I am keeping mine for the third year so far, as I am not so much impressed by megapixels and marketing brochures.