Nosism (NO-siz-em) noun: The use of 'we' when referring to oneself.
Nosism is also called the "editorial we" (because used by editors) or the "royal we" (because used by royalty). One web owner explains his use of 'editorial we' thusly, "The editorial 'we' is used to express the belief that others guided by the Spirit of God may share" in his view and purpose.
Though he was wrong, Mark Twain once said, "Only kings, presidents, editors, and people with tapeworms have the right to use the editorial 'we'." Good humor, but he left out the fact that God can use 'editorial we' and can inspire anyone He wants to use it as well.