I think that a significant effect of global pop culture is that there is a certain amount of shared experience that enhances what it means to be human in the modern setting.  The sharing of pop culture through means of the internet and the purely global stage in which pop culture emerges helps to make its appreciation something of universal implications.  The growth and proliferation of social networking platforms and information technology venues have helped to establish pop culture as a global phenomenon.  In some respects, this has helped to make the world, "smaller," to an extent, because what is seen as "pop culture" in one part of the world can be easily appreciated as so in another one.  The effect of this is to bridge differences.  In remote parts of the world, should a good internet connection be present, what is loved in industrial centers can be embraced.  This effect of "shrinking" our world can provide a type of starting point in recognizing the similarities that human beings share, as opposed to differences that might potentially divide.  This is not to say that a pop culture icon like Madonna can bring about world peace.  Yet, it is to say that the effect of pop culture being embraced from a global perspective with the assistance of information technology helps to bridge the divergence in the world and find a point of convergence.  This becomes a significant effect of global popular culture.