I don't really believe any game is truly non-linear, but that there are some that excell in it more than others.
In GTA3 you are usually given objectives with very few restrictions on how to achieve them. The broad array of options encompasses not only weapons, tactics and your interpretation of the storyline (Such are the limitations in Deus Ex) but even mission planning and the general style of execution. Though of course the objectives are very simplistic and the storyline is facile and trite compared to Deus Ex's.
I think the ultimate non-linear paradigm is to create a game that evolves according to your actions, and not just merely accomodates them like in most "non-linear" games. But this would be difficult if not impossible to implement within the current state of computer AI and as stated, testing procedures.
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This comment was edited on Jan 21, 00:09.
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