How about abandonware ? Not exactly legal as far as i know.. especially when stardock had to try and obtain the rights from someone.. and if it is still being sold...
The right to the IP doesn't mean that they have the rights to the old, actual, game - as far as I know, of course.
It's abandonware. It's a seriously "grey" area that no-one care about. It's not "exactly" legal, but it's not "exactly" illegal either, since no-one enforces the legality, or persecutes the abandonwarists (normally). I'd say that it's definately Stardock's call if it's alright to have this on their forums, but seeing how abandonware is generally impossible to find or buy with anything short of Piracy, the morals of the matter is entirely clear, at least to me.
Anyone who whines about abandonware being "illegal" should be keelhauled like the landlubbers they are, yarr.