I just bought a 5D II and found the focus to pick up whatever point is closest to you ignoring any center weighted focus points. For example with a girls elbow in the picture it is in the lower 1/3 of the frame , thus the center just under the face and the camera is focusing on the elbow.
Someone I saw today said to calibrate each lens to the body. Still it is focusing , just on the nearest point, rather than the center on my set up which is a 5DII fmwr 1.07 and 100mm macro.