https://bulbagarden.net/threads/movie-10-dialga-vs-palkia-vs-darkrai-discussion-thread.16154/
So, the 10th anniversary of the anime is coming up (April 2007), and so is the tenth movie (but not the 10th anniversary of the movies - that's July 2008)...
dialga vs palkiadiscussion threadmoviedarkraibulbagarden