Some of Hinckley's prophetic accomplishments have been:
Protecting the youth of the church against the evils of having more piercings than God desires: one set of earrings for girls and none for boys.
Admonishing Mormons to ignore their doubts about the church and focus instead on reminding themselves that the church is true despite what anyone says to the contrary.
Never making an official pronouncement of doctrine on difficult matters such as Brigham Young's Adam/God theory and statements about the necessity of polygamy.
Being fooled by Mark Hofmann's forgeries of ancient documents.
Assuring Larry King and others that Mormons don't believe men can become Gods, when all past prophets since the 1830s have believed and taught this.
Informing King and others that Mormons have no longer have anything to do with polygamy, when it is in fact still believed by most (and there has never been an official pronouncement to the contrary) that it is to be practiced in heaven.
Gordon B. Hinckley is a PR man