360
Insiders say cutting-edge graphics are too costly for AAA games
(www.tomshardware.com)
This is a most excellent place for technology news and articles.
Also, interactivity. Both games you mentioned have unparalleled interactivity when compared with the triple A space.
Not saying it's necessary, but at a certain level of fidelity/realism it starts to look really weird when the world doesn't meaningfully react to your actions.