Well, it's all depending on where along the line the development is.
During initial development, you can never know what's going on.
take 3d clickable cockpit for example, Admin has stated in the past that it's on the menu. there are over 3000 clickable points spread around the shuttle pit. how much CPU overhead would be the detection system? or the added graphics, how much impact would that have on the Graphic card.
I can assure you, knowing how the dev team think, this would not be FSX type resource hog. it will run on normal current PC. (dual core something with a basic graphic card - I'm not sure what with onboard stuff) - If you would be able to run the thing on "Ultra-high" on this type of rig, only time would tell.