I (IMHO) wouldn't think that we'd be seeing this kind of thing in the first commercial release of TG2 and if this stuff is planned its probably some thing that maybe seen some time in the future on the list of to dos like a waterfall system and procedural star-field generation, as some one who likes art by Tim White, Jim Burns and Bob Layzell any thing that would make the creation of such imagery easier would be welcomed (But I know, Terragen is not meant to be a space phenomena creation tool and so on and so forth), but what we want and what we get are two different beasts altogether.
Who knows when home computers are powerful enough it maybe possible to entire photorealistic procedural galaxies, accurate down to star clusters and planetary systems but that is decades in the future and probably in our life times, but maybe in the life time of our children or theirs, we can but dream.
Regards to you.
Cyber-Angel