I think that I read this somewhere before, but this article goes into detail about the benefits of running barefoot:
Scientists have found that those who run barefoot, or in minimal footwear, tend to avoid “heel-striking,” and instead land on the ball of the foot or the middle of the foot. In so doing, these runners use the architecture of the foot and leg and some clever Newtonian physics to avoid hurtful and potentially damaging impacts, equivalent to two to three times body weight, that shod heel-strikers repeatedly experience.