I'm guessing the Diamond/Pearl subforum will be renamed the Diamond/Pearl/Platinum subforum.

By the way, you say the pokémon captured will be the same...let me post some info I found I-forget-where. Probably Serebii. It's the version-exclusives for Platinum.

MURKROW AND MISDREAVUS
These pokémon are counterparts in Diamond and Pearl. Platinum has NEITHER.

GLAMEOW AND STUNKY
These pokémon are counterparts in Diamond and Pearl. Platinum has NEITHER.

TRAPINCH
This pokémon in not in Platinum.

CLAMPERL
This pokémon in not in Platinum.

THE LEGENDARY BIRDS
These legends, unobtainable in DP, will wander Sinnoh in Platinum's post-game.

THE LEGENDARY GOLEMS
These are obtainable only if you have a promo item from the 11th Movie. Pbbth.