Ray Tracing in a space game would be kind of a waste. It does best when there's something to reflect off of (water is a great example) that shows what it is reflecting.
Well, you dont have to use it for reflections, naturally thats a waste in environment with nothing to reflect Although, suns, planets, nebulae...
Anyway, i was more thinking about raytraced shadows, global illumination and stuff like that.
Bottom line, RT or not, i hope for some proper eye-candy. The way the upcoming Falling Frontier game looks, would be a good starting point - i mean, the way stuff is lit and the quality of texturing on celestial bodies in that game is the level i would like to see in Sins sequel.