Design Director Michael de Plater, while speaking to the folks over at IGN, has said that certain features of Monolith's newest game set in the Lord of the Rings universe will be scaled back for current-gen versions.
Specifically, de Plater stated that Shadow of Mordor's Nemesis System, which governs enemy AI, is "just so huge", and that the older systems may not be up to the task. The Nemesis System is Monolith's solution to enemy AI in the game, allowing enemies that the player faces to each be a unique individual, with personality, strengths and weaknesses that are unique to them. Enemies are capable of doing tasks off-screen in this system, even growing in rank between encounters with the player and remembering previous interactions.
Understandably a hefty load of the software would need to focus on this system, and as such de Plater has said that they are focusing on PS4 and Xbox One platforms foremost, and then trying to get as much as possible from the current gen versions. He has reassured players that the core of the game will remain the same across all versions, with controls and gameplay unchanged. What they won't have, as de Plater explained, is the "same level of depth and variety and simulation within the Nemesis System."
This is perfectly reasonable in our opinion, as developers make the slow transistion from one generation of consoles to the next. Still, at least they are trying to deliver as much of the core experience of the game to those who have yet to make the plunge and purchase the newer systems.