It works because they can't put the genie back in the bottle. They've now committed to supporting this open protocol and for them to try to take it away would m

It works because they can't put the genie back in the bottle. They've now committed to supporting this open protocol and for them to try to take it away would mean breaking thousands of websites. Therefore others are free to build on top of their work without fear of the carpet being pulled out from beneath them. As to relinquishment, it's a non-issue because Facebook owns nothing to begin with. Users pay attention to whatever suits them best, and when something comes along that does it better than Facebook, well they'll just use that instead.