requirements for 1080P should be fairly easy to reach. granted the poly counts of individual object is maybe 3 to 10 times the current game content, but the effects aren't as demanding since it's in space. tessellation, volumetric fog, and various other effects like grass and wind should be less of an issue as opposed to planetary / atmosphere environments. what it really comes down to is how populated each area becomes in combat. if you keep things to less then 30 or 40 ships, most modern system should be able to handle 1080P however going beyond that will result in server/network lag more so then your computers ability to keep up with graphics.
as far as OCN people are concerned, network lag will be the biggest game killer for star citizen IMO.