We've had this debate for a long time and i'm sure its never going to stop.
Size only matters if it matters to you. But, it seems that guys with smaller penis' are hung up because they think god short-changed them, and guys with larger ones like to brag because they do. Not unlike gals with small breasts want bigger ones, etc.
While laides can get breat augmentations, men cannot go into a plastic surgeon and get 3" added to their cock. Penis pumps and pills do NOT add lenght or girth - you got what you got.
And yes, sexually satisfying your partner is NOT only about how big his cock is, but a combination of love and affection, technique and confidence - tit and cock size are what they are.
How do you measure?
http://www.sex-project.com/measure.shtml
http://www.the-penis.com/size.html
http://nawtythings.com/penis.html
Just some great sites on the the issue!