The article certainly does more justice to the topic than any summation I can provide, but in the words of the authors, "Physiological changes in the brain - an altered volume of tissue in some areas - occur through meditation. Practitioners also experience beneficial psychological effects: they react faster to stimuli and are less prone to various forms of stress." They also provide an excellent chart regarding the areas of the brain stimulated by meditation by using neuroimaging.
I never meditated primarily because it made no logical sense to me. Always being a constant, vivid thinker, why would I need to clear my mind when 99% of the time I liked what I was thinking about. I'm second guessing my decision now. Do you meditate?