Very important title for your question My website has a user-centric. Title and text to be edited by users. 1.My big question is this: (title and url changed by users like wikipedia) url: http://mydomain/serial/18/dexter Code (markup): url(title)after change by user: http://mydomain/serial/18/serial-dexter Code (markup): If the page does not change dexter and later by other users serial dexter In terms of SEO, there is the problem? wikipedia how this problem is solved? 2. The second question (duplicate title and content but important in 2 page) If there are two pages with the same title and how can this problem be solved? http://mydomain/serial/18/dexter/news/1 Code (markup): http://mydomain/person/12/micle-chal/news/1 Code (markup): That's because the news relate serial and the person concerned. (Google Translate)