I agree that the definition of "effective change" depends on how the leader defines "effectiveness."
That is precisely why strong leadership and role models in the area of social entrepreneurship are so important. I think that the concept of bringing together the notions of "social good" and "entrepreneurship" are still relatively nascent, and sometimes it can be difficult to quickly and easily identify leaders in the field.
It will take a few visible, successful pioneers in the field to establish the concept more firmly. If you haven't yet read
Malcolm Gladwell's "The Tipping Point," I highly suggest the book. It discusses the spreading of trends, including the importance of early-adopters and people who connect a large number of people to each other to facilitate adoption. I think that the book has broad implications for leaders in various disciplines, including entrepreneurs, policy makers, and trendsetters.