I had a go with the beast today and like everyone else was pretty impressed. The screen is very nice and the ability to zoom to 100% or more and then pan around is really useful.
Assuming that the 80mp version has the following IQ benefits compared to a P65+:
* about 1/3rd better DR
* the extra resolution of 20mp more
* slightly lower noise
I wondered whether the upgrade might make sense for me.
My take is as follows (I won't repeat what LL and Jack and Guy and Uwe and others have said...) and takes into account that the upgrade cost from P65+ including tax is likely to be in the region of £12,000
For tethered, studio use only, I wouldn't bother upgrading. I don't think I've ever needed more resolution, however tempting it always sounds, and with flash in the studio I am shooting at low ISOs and with very carefully controlled and monitored exposure, so the noise and DR benefits are probably marginal. The benefits of the lovely new screen are largely obviated by tethering, as long as you can get your monitor near your camera.
Therefore, for me, the reason to upgrade would all relate to outdoor and non-tethered shooting, where the benefits of the new features could really kick in. Now, it is too early to judge this because the units we have all used are prototypes and things will get faster and more feature rich but my initial take is that one would truly have to see the shipping version before placing an order. Why? Because on the prototype, with the CF card provided, there was a 10 to 12 second delay between pressing the shutter (and then double clicking the screen as soon as it displayed the shot) and the moment when you could see the fully resolved 100% zoomed image.
I have no doubt that that will get much faster.
Shooting non-tethered, the critical improvement of the new model, especially when mounted on a technical camera, will be: (for me)
* easier framing (doesn't need more than basic live view but does need it to work in bright daylight, which current model live view doesn't really)
* ability to set and check focus accurately, especially with movements.
Now, there is no implementation in the prototype of the Live View or the Focus mask, nor (I think) any clear indication that the focus mask will work in live view mode or that live view mode will be zoomable at full res. Let's assume for a moment that there may not be a real step-change in quality of live view from that available tethered on a P65+. IF that is the case, then for my money, with or without focus mask, it might be of limited use. For me, therefore, the process of setting and checking focus with movements would require a noticeably faster time from shot to full res full zoom view than we currently have in the prototype. When the light and the weather are changing and I am trying to get everything right (and take LCC shots too!), working in the field with movements needs EITHER good zoomable live view, preferably with focus mask, OR very fast full res review.
SO, much as I really really loved the look and feel of the new model (and really really like the simple fact that the back can be powered on by the camera body!) I won't be placing my order until I've seen the shipping implementation.
I'd imagine most people will be in the same boat. But for me the question is, will the 'early adopter upgrade pricing' window close before I can try a shipping version?
I know I want this new back... but I can't yet tell if I need it! But boy or boy, does that screen look great, and using it feel natural...