Dude... uh... Bioshock was a successor to the System Shock games in spirit only. Notice how the former was set underwater in the past and the latter was on a spaceship in the future, among other key differences. In addition, I believe there already was a System Shock 2, so I'm not sure what an "unmade SystemShock2" would be. Care to explain, please? Perhaps I'm misunderstanding.
EDIT: Gah, spent too long on Wikipedia and got ninja'd. Point stands, however.