It looks like the post-rotation format has been officially announced. Take a look at the official announcement at Pokemon.com.
Here’s what the new format will include.
- Diamond & Pearl—Majestic Dawn
- Diamond & Pearl—Legends Awakened
- Diamond & Pearl—Stormfront
- Platinum
- Platinum—Rising Rivals
- Platinum—Supreme Victors
- Platinum—Arceus
- Rumble
- HeartGold & SoulSilver
- HS—Unleashed
- HS Trainer Kit
What do you think about that? Personally, I’m disappointed. I was hoping for more of a clean slate to start working on new decks. The metagame will shift, but it doesn’t look to be a major change.
Pikkdogs 
Joel