Hawk, it's great to hear your input, but to be entirely honest:
Hi all one thing I think we forgetting is in home world the cpu did not have to also deal with income from a vast empire and all the ai that goes with that as well as pirates and black market as well.
The map size of home world and home world 2 and home world cataclysm well local,
Why are you bringing this up again? Homeworld has passed out of the discussion. We've established that there's no real reason we should compare the games, simply because of the scale. Though I seem to disagree with Heflys on most points here

I agree with him that confusion tends to set in.
The people arguing for movable turrets, as I understand it, are NOT arguing from the point of view that "if HW2 could do it, why can't this?" because that argument is clearly a fallacy. Here the question seems to revolve around:
1) How can the turrets be made to rotate? Clearly there would be a need to change meshes etc. (The fact that HW could do this was simply because it had an engine and ship designs to be able to do this, so we can't compare it with Sins)
2) Would rotating turrets slow down the computer, and if so, is there a way we can mitigate the effect towards the minimal?
3) If not, then can rotating turrets be made an option?
Whether or not the devs decide to do this is up to them, though they said they listen to their customers. Whether or not it is plausible, is, again, up to the devs. I'm sure if they got enough wails from us ungrateful customers they would consider putting it in a major update or expansion.
a few more clarifications. What I would be looking for is a weapon type of animated turret, it would be used in specific situations where the turret dominates the profile of the ship or would look exceedingly out of place to not rotate (small guns can be eliminated or simplified as mesh detail) these would be weapons similar to the main batteries on a Iowa class battle ship for example. They would be intended for supercapitals only. Realistically this would be an option for modders and for the IC devs to have some impressive visuals for big weapons (and I wouldn't rule out that the system currently exists for some specific weapons in the release version .... )
I think for a game like Sins, rotating turrets are unimportant enough to apply to the supercapitals only. Perhaps any firing delay would only have to apply to them - I agree with Eviljedi. His next paragraph is the embodiment of why Lightzy's solution of preset firing delays are elegant (please correct me if I'm wrong). Edit: ...so we don't need to quote that paragraph.
as my understanding, sins is using a different model for weapon damage that calculates damage per salvo, not per shot, since this is the case the damage rate is more like a damage per second than a direct reduction, the muzzle flashes and hit effects are already significantly desynced from the damage. The damage is not tick tied by a muzzle effect, a projectile intersection or a hit effect, the animations are played to cover the sudo-dps model.
Which, of course, would make it possible to animate the turrets with no detriment to CPU calculations, though first salvos on small craft would look odd as those craft would simply blow up with no clear reason.
Like either Heflys or Annatar said (forgive me - I can't remember which) or, indeed, implied, EvilJedi seems to be more of an authority on this than most of us, given his experience with the Warlords mod.
Forgive my annoyance; I just don't see why we're still comparing HW/2 with Sins.