The official Pokémon movie website has updated. Translations follow:
Further Special Pre-order Ticket Information
If you buy the special pre-order ticket at the theater, you'll be given an "'Always Together!' Satoshi's Pikachu Cell Phone Charm"!
"Pikachu is with me wherever I go!"
Theater-exclusive!
This charm will be given to 300.000 buyers total across Japan!!
*This is a freebie limited to theaters.
*Each theater will have a limited number of freebies.
*You will be given one charm for each pre-order ticket you purchase! (Parent/child pair tickets come with two charms)
*This freebie is not for sale. Please refrain for purchasing for resale purposes.
*Please contact theater staff for details.
Source:
http://www.pokemon-movie.jp/tickets/