It will push to other servers if you reference those sites in your content. So if I link to juligasa.com in my document, then we need to make sure juligasa.com has the backlink, so we also push there. I now mentioned Julio in this note, and I am now sending his peer:
By default, yes. But it will push to a different gateway if the user has chosen a different one in settings. Centralization by default, but not mandatory!!