I really liked this too. Perhaps this is most positive yet? I read as if you almost liked it!
I find your theory very interesting; that Linearity is okay if the player is not control of any "strategic planning" and just follows along doing the lowest of tactics only. Did you feel that because if this, the cut-scenes did not feel like dragging you out of the experience? What I mean, is that you thought of your role in the game in such a way that letting the ingame character taking care of talking, etc game natural? And if so, did you still find the game as immersive as something more non-linear?
And now I have yet another reason to get hold of a ps3...