The official TV Tokyo website was updated today with information on an upcoming episode of Pokemon Sunday that will air on Sunday March 15th 2009. The synopsis of the episode indicates that an announcement about this years movie ticket promotion Pokemon will be made on the show. (今年の映画前売り券につくポケモン発表！).

The title for Pokemon Sunday 230 - 'News on Preordering Tickets for the Release of this Summer's Pokémon Movie & A look at the First Public Release of Arceus in the Game' was announced at the end of today's episode of Pokemon Sunday. From the way the title is worded, it appears that Heatran is going to be the pre-order movie ticket Pokemon this year and Arceus will be the public event Pokemon. The announcement is expect next Sunday and we will confirm the speculation at that time.

Source: http://www.tv-tokyo.co.jp/program/detail/18687_200903150730.html