Square Enix wants to celebrate the 25th Anniversary of Final Fantasy with a teaser portal site.
The site currently just has links to all the numbered Final Fantasy games, and to Theatrhythm Final Fantasy and Final Fantasy Brigade. There's also a link to information about a 25th anniversary concert that will be held in London on November 2. See this page for details on the concert.
Link to 25th anniversary: http://www.finalfantasy.jp/ff25th/