If you've read @Dan's post about Steemit's Evil Plan for World Domination, you will see that the founders of Steemit envision many Internet powerhouses such as Reddit, Facebook, Ebay and Paypal being directly challenged by Steem powered businesses like Steemit.

When we are able to provide a similar service and the profits stay within the community instead of being distributed to a small group of shareholders, the potential is enormous. Wikipedia is already a nonprofit, so there's not much incentive to replace it.