Is it highly resource demanding?
Relatively.
Do thrusters produce light?
No comments. I want to keep some surprises surprised.
how are those ring particles created?
Point octree, with points following camera.
Could it also have assorted lights around the bases lighting them up (even better, the ability to activate a base/pad from ship - some aircraft have this for runway lights on secondary airports n it's very cool).
Assigning 1-2 lights to a base is doable, but this is not deferred shading - 4-8 lights is global limit or you get a slide-show on all but best GPUS.
How about the asteroid belt? Or is that asking too much lol...
What about it? It's not as dense as in Star Wars, by an order of many magnitudes.
While I'm adding wishes... any chance of animated astronauts (ie such as walking, moving hands/head etc)?
That is common add-on developer's business, possible in current version.
Any idea when it will be finished?
There was an intended release date of Christmas 2008, but since that wooshed by there were no comments by Martins. And untill Orbiter 2009 is out, no OVP.
earth shine effect, which lightens the spacecraft in LEO
Doable, but it's something that will take some research, as just slapping a light on would probably be unrealistic.
eclipse shadows (if possible with transparent edges)
Rather complicated to do, but if there are in Celestia it could be doable.
Already present in inline client, to be done in OGLA.
normal mapping for planets and moons, though would be cool for spacecrafts too. This is actually obsolete if orulex is going to replaces the spherical planet meshes.
It goes to, and it's generally less resource-consuming than normal mapping on a planet-scale.
animated textures (for things like moving clouds, volcanoes on Io and exhaust textures)
Doable, but where will you get the animated clouds, and how much space will they consume?
Animated ground textures - tricky, need a good reason to try doing it.
Animated exhaust - simple, but no core interface. Could be done in current version as well.