The just-announced Chan-Zuckerberg Initiative may change the face of high network giving, as rather than granting funds to an outside entity they acted to give to themselves.
The CZI was structured as an LLC which does give up some tax benefit but in return gains certain freedoms, like the ability to lobby legislation, engage in public policy discussions and to take part in for-profit initiatives close to the core business. This is not something that a non-profit organization can do.
One note of caution if you find yourself in the situation of considering an initiative like this is public perception. The idea of a for-profit may remove the luster from the traditional public appreciation of great philanthropy.