As I've read the comments here, I've realized that I really don't like the idea.

This puts: a) A lot of power into the control of Github b) changes the entire incentive model for FOSS development c) devalues the aspects of a "sharing economy" and "co-opetition" that FOSS has grown.

My question: Will a sponsored person be able to see who has donated to them? That should be kept anonymous. Otherwise people will be able to "buy" the feature they want over others. Community interests will be lost.