I have been flying for a few hours, and here are my first impressions, fwtw.
System: i7 2660 overclocked to 4.5, 2X 570 GTX in SLI (not used yet, I know), 5780x1080 on three screens, 8GB memory.
First, the frame rate limiter is very important in this sim. It never was for me in FSX. If I set the limiter to unlimited the view is very choppy with numerous stutters. Set at 30 it gets about 26fps with autogen set to dense across the board. Ground shadows being set high lowers that to around 18fps.
The clouds and sky effects are nice, the water is a little strange for my tastes.
Megascenery works fine, but oddly it doesn't run at any faster fps then default, even with all autogen turned off. I will have to figure that out!
The Ceranado planes are nice, some of the defaults are not so nice.
Saitek flight yoke, throttle and pedals work fine. Panels so far do not. I'm sure there is a work around either out there or coming soon.
If this were released as MSFS 11, I think we would be disappointed. Out of the box the product preforms very much like FSX. The interface is not a step forward, but that is just my opinion. The frame rates seem lower to me, when trying to compare apples to apples. But we are buying this for the future. Hopefully third party developers will bring the sim up to its potential.