The Growth of Social Media
I just discovered this INFOGRAPHIC after some prompting from writer Luca Tiralongo. Notice the steep curvature in user growth-rate across all demographics in every aspect of our lives.
It was published mid-2011, so you can assume that the data has changed since in all cases, and most likely in a way that strengthens the point.
Has social media changed the world?
Undoubtedly.

Source: The Growth of Social Media: An Infographic
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