I like Linear over non linear mainly. I have found that the linearity of a game is proportional to the quality of story telling (for me that is). The more linear a game, the better (or better chances) the story will be while the more non linear it gets the shittier the story tends to be. Just my personal experiences with the matter, I never understood why some people wank over the thought of a non linear game as they tend to be rather shallow in my eyes. It also gets annoying when people have the sack to complain about linearity in one game and then go off and play another linear game making the whole thing very nerve racking.