Daedolon: Sequel released first, forum titled "System Shock 2" (and not "System Shock Series") and a few other things amount to me not holding my breath.
The forums are often named after the first game of the series that came out if the rest is not already on the horizon. But normally they are renamed later after more releases (the Wing Commander forums were called Wing Commander Privateer for a long time i.e.)
And I don't think it is a problem of getting it to run, it ran flawlessly in DOSBox without any work when I tried it some years ago. I only have the Floppy version, but I don't think the CD release is harder to get it to run.
I think the only problem the prevents GOG from releasing the game for years is the same as with the second game: a rights chaos.
Hopefully someone sorts it out soon, I want to play the CD version of System Shock 1 and it is pretty expensive on ebay etc.