Update (7:00 PM) – Added a bit to the end of the second paragraph.
Australia’s official Pokemon TCG distributor has just released a preliminary product sheet for Next Destinies! It reveals that the set will feature over 100 cards, that Mewtwo-EX, Reshiram-EX, and Zekrom-EX will each be included, that six Pokemon-EX will be featured as full art cards, and that the theme decks will feature either Reshiram or Zekrom! You can see the logo above, which emphasizes the “X” in “Next” to symbolize the return of Pokemon-EX.
In Japan, there are only eight Pokemon-EX that have been released, all via Hail Blizzard / Psycho Drive and the Reshiram EX / Zekrom EX Battle Strength Decks: Shaymin-EX, Kyogre-EX, Mewtwo-EX, Kyurem-EX, Groudon-EX, Regigigas-EX, Reshiram-EX, and Zekrom-EX. Except for the last two, the other six Pokemon-EX all have full art cards, meaning we will have to get those Pokemon-EX in our set! And since we know Reshiram-EX and Zekrom-EX are confirmed in the set, we know we’re getting them too, meaning that all eight currently released Pokemon-EX in Japan will be included in Next Destinies! (All of this assuming we don’t get any future Pokemon-EX to replace the ones above, such as Darkrai EX from Dark Rush, which will probably have its own full art version. If there is to be a RSE remake next year, TPCi will probably hold back Kyogre-EX and Groudon-EX, especially since Rayquaza-EX will be coming out in Dragon Selection. If this does happen, we would get two “future” Pokemon-EX from either Dark Rush or Dragon Selection instead.)
As you have seen in this article, the new Pokemon-EX will have a hyphen between the Pokemon’s name and “EX” and “EX” will now be capitalized (e.g. Shaymin-EX, Regigigas-EX, Kyogre-EX, etc.). Pokemon-ex from the EX sets of Generation III simply had a lowercase “ex” after their names without any hyphen (e.g. Kyogre ex). In Japan, the new Pokemon-EX are distinguished from the older Pokemon-ex simply by uppercase “EX” instead of lowercase “ex.”