When panning, do you try to position yourself perpendicular to the object or are you slightly at an angle? What changes do you make when photographing a fast moving car/boat vs. a football player --I realize the speed of the pan will change -- how about aperture and shutter speed?
I try to follow the moving object with the camera at the same speed. This will blur the background while maintaining the sharpness of the moving object. A shutter speed of 1/15-1/20 will blur motion while a slower speed will increase blur and a faster speed will decrease blur. I generally set the shutter speed first then set the aperature accordingly. Shutter speed is more important than aperature when panning.
Great picture! I have the same boat minus the radar which I am adding in 2008. Had mine offshore and they will take more than most people can handle if you do not mind being in a boat that size they are super safe and strong.