It's all a moot point now, as far as the 5D3 is concerned....
But, in some respects it's a matter of where Canon might have done "more than necessary" as much as "what's missing" from the new camera... For example:
I would have been happy with 19-point AF (similar to the 7D), or perhaps 26-point... Especially if it would have kept the price more comparable to the original list price of the 5DII ($2500-2700 if memory serves). Just about anything would have been an improvement over the "horse-drawn buggy" version of AF that was in the 5D1 and 5D2! I suppose Canon felt they needed to pull out all the stops with the AF system, in light of what the competition has been offering. But "more" is not always necessarily "better". I suppose in the end it might have been more cost efficient to simply use the same AF as in the 1DX, than to produce a separate, lower spec system just for the 5D3. As it is, it will be fine I'm sure. And it's bound to be an improvement... way overdue.
Along the same vein of keeping the cost in line, 5 fps would have been fast enough for a camera of this type. I also wasn't unhappy with the 98% viewfinder. Hey, 6 fps is nice... we'll take it. And, hey, 100% is nice, but undoubtedly adds some cost, size and weight. Not complaining about either of these specs... If it would have helped keep cost down, these "goodies" would have been lower priority to me.
I'm trying to be realistic here... $1200 FF just ain't gonna happen. But $3500 US does seem rather rich. I'm not sure 5D3 is "$800-$1000 better" than 5D2, or if it's worth $500 more than a D800. (Unless Nikon raises the price on their camera, I kind of suspect the street price of the 5D3 will need to drop pretty quickly... after all the early adopters have paid top dollar for theirs and stock of the camera in stores and in the pipeline normalizes a bit.) I guess we'll find out.
I'm surprised the camera didn't end up with more resolution. Competitively, Canon is going to need to produce something in the 36MP range sooner or later. This isn't a deal breaker for me, though... I'd rather have top quality 22MP and higher ISO capability, than gobs more MP that compromise on some of the quality and speed factors.
Not having ever used a camera with Digic V+ processor (supposedly 17X faster than Digic IV), I don't know what that will do for AF performance. But an alternative route to improve AF performance might have been a discrete AF processor (as is done in 7D and 1D series). Maybe this isn't necessary with a Digic V+ in a 22MP camera that tops out at 6fps, though. We'll have to wait and see.
I also would have really liked to have seen an articulated LCD on the back of the camera. I'm not a video shooter, but it would have been really handy for high and low angle still shots too, a really nice complement to Live View. I know some folks don't like articulated screens, but they can simply not use it. Those who would like it are now in the position of having to buy a different camera, or work tethered to a computer, or fit a third party LCD, or use an Angle Finder in situations were that's possible. But I also like that an articulated screen can be flipped face inward to better protect it during storage, or while shooting to keep "nose prints" off it, or just to eliminate a possible distraction while shooting. An articulated LCD might have made the 5D3's list price a little more palatable.
Yay, Canon, for expanding bracketing up to 7 images! Long overdue! That will be handy for HDR, among other things. But, hey Canon, why didn't you match the competition by allowing up to 9 images (or more)? And, how about offering focus bracketing (such as for focus stacking)? Wouldn't that be cool? Sure, I can install Magic Lantern s'ware to accomplish this... eventually (it will no doubt need to be rewritten for 5D3, so will lag the camera roll out by some months at least). But it would have been nice if Canon had thought of this.
Dual memory cards.... cool! I'd have preferred both be Compact Flash, instead of mixing memory types. Sure I can see the argument for different types... if using one as your primary, the second for backup.... or one for RAWs, the other for JPEGs... different types of memory might make it easier to identify which is whichthroughout your workflow. But personally I just don't like having to buy and haul around two different types of memory. And I'm fine with the size/format of CF, not a big fan of the smaller cards... I'll worry more about dropping or losing them... or accidentally letting one go through the laundry in a jeans pocket. I was a bit surprised, too... Canon finally stopped using different card types in the 1DX. They'd stubbornly mixed CF and SD in all the earlier 1D models. The 5D3 seems like a step backwards, or perhaps separate design teams that don't talk with each other, or a company that doesn't have a game plan in place. (And, meanwhle, Nikon has flipped on this too... I think all their dual card models have consistenly used same-type memory up to now. CF in fact... Until the D800, which also will have a mix of CF and SD.)
Definitely didn't want a built-in flash, wireless flash control, WiFi, or GPS... those are all things that are much better done with optional modules, as needed. For example, ST-E2 is fine for folks wanting to control off camera flash (doesn't make obnoxious visible light flashes or overheat and shut down until it cools down, the way in-camera wireless flash control does on those cameras that have it). The ST-E3 will be even better, a big Bravo! to Canon for finally starting to transition to radio triggering and control, getting away from strictly line-of-sight limitations of IR. Either of those modules can also serve to provide focus assist in low light, too.
I have no opinion one way or another about video capabilities... I use my still cameras for still photography, not video. However, I was under the impression that Canon had video specific, EF mount cameras in the works. I'd think that movie makers and professional videographers would be more inclined to look at those. And would be surprised to see a great deal of additional video development in the DSLRs, beyond what a reporter might need for some online video or brief television news clips. But, hey, this sure isn't my area of expertise!
I've only seen one image showing it, but the new grip for the 5D3 appears to have a secondary joystick... Bravo if it does! (Boo, if it doesn't!) If it does, they really should have more pics of the back of the grip out, for marketing purposes (the front of the grip looks like every other grip... it's the back of the grip where something new is happening!)
It's obvious from the photos of the camera that the mode dial has a lock, similar to what's on 60D and can be retrofitted to 5D2 and 7D.... another Bravo! for that.
Only have sketchy info about the new WFT... but it appears to not be model-specific, so it might work with future models (and not need to be replaced if one upgrades cameras). And, if this is the case, unlike earlier models it doesn't replace the vertical/battery grip, reducing the camera to relying on one rechargeable main battery and making battery swaps a pain. If so, that earns Canon another Bravo!
I'm reserving judgment about high ISO performance, general IQ considerations, and even to some degree resolution, until we see a whole lot more "real world" work done with the new camera. Most of the other stuff is actually relatively minor by comparison... Ultimately these are the most important factors.
Not sure about some of the new buttons... We'll see how useful in-camera image rating will be. The new DOF preview button is a good idea and better located. The control layout looks to be generally similar to 7D, which is fine. I stopped whining about having a dedicted MLU button... Live View serves the same function in all situations I can think of where I'd want to use MLU (but still would be better if the LCD were articulated).
I'd like to see all Canon DSLRs including future 5Ds have a momentary "high frame rate" button on the grip, so that the camera can be left in single shot mode most of the time, but can be nearly instantly switched to it's highest frame rate, on demand, if needed. Often you don't have time to switch back and forth, when there's suddenly a need for a quick burst of shots. The alternative is to leave the camera in the high frame rate mode all the time and try to minimize the inevitable, accidental extra shots. Heck, Canon built a momentary high frame rate button such as this into the motor drives of their film cameras back in the 1970s (the MA Motor Drive for A1 and other models, for example)... One would think it would be even easier to do this on the DSLRs.
Another button or control that would be nice.... One that somehow prevents posts on blogs and forums about the camera until people actually have it in hand and can give authoritative info based upon real world use.
So, I just gotta ask.... Should I buy the 5D3 now, or wait for the 5D Mark III"N" or 5D4? 