Ok stop here right now. The P65+ certainly does not block up shadows earlier than any other back I have seen. Nor do I believe that the S2 is better. Let's say I haven't seen prove for that.
"You could see the shadows blocking-up and the foliage getting a little smeared in the P65+ shot and a similar shot on the S2 was crystal clear"
Sorry but that sounds like wrong processing. I can't say for sure, but is sounds, like the default Noise Removal was on. Which in C1 I think is still the BIGGEST mistake you can make. If you do that you can get better results with every camera in Lightroom ^^
So back to the topic. I haven't read everything, but I will try to give my few point.
I have P65 + phase camera system 45,80,150 as lens and my loved LF system with 23,40,90,150
Than there is my Canon System which is a 5DMk2 with way to many lenses.
There is the Leica M9, which well is just great and fun to work with. Lenses for most work: 16-18-21, 28 2.8, 35 2.5, 28-35-50 and a 90
So now let's get back to the S2. I love how it feels and shoots. I can't say anything about it's image quality, however I can say, that it won't and CAN'T replace a P65 + LF system. So it can't replace that. So now what ? Could it replace my Canon System ? I fear not. As much as i hope for it, I fear that ISO 800 is the limit. Which just gives me one more stop than my Phase System.
So for now I'm planing to do the following:
Probably replace the 5DMk2 with a 7D. Sell most Canon lenses. So that I am left with a handful.
Wait till next year, wait until Leica can ship the 30-90 for the S2. Get a S2 System from my dealer with everything I would like and want and try it out.
At that point I can perhaps decides whether it makes sense to buy one.
At the end I want to address one point. the FUTURE.
I think it is a risk to drop that much money on a S2 System. The same money could be used for probably two generations of Phase upgrade price and in addition for a new 1DsMk4 when it comes out. So for me the price is one main point holding me back. It is a lot for something that can't do anything better really.
Now before people come at me again that the S2 will be so much better than a 1DsMk4 with 30Mp. Well really ? I have enough lenses which are good enough for 30Mp in such a small sensor. I know you won't be able to use a crappy lens like the 17-40 or 24-70, but my Leica, Zeiss and Top Canon primes will hold up pretty well. Now we come back to the file quality question. Here i have a different opinion. I don't care that much as long as i can print the size I want and it sells.
Bottom line, I would wait and will wait. I want to know what really happens before spending so much money on a new system, even if it has a RED dot. ;-)