Diamond. It is my first and only Pokémon game, and Dialga is blue-colored awesomeness!!!!!!!
PLATINUM -evil laugh-
one of my favorite pokemon games
Platinum, mostly due to the Distortion World.
Platinum because of the things post elite 4. And plus Dawn is a playable character XD
It was, is, and always will be Diamond for me. I'll always have a soft spot for that game. Such memories... Ah, four years just fly on by, don't they?
Platinum was by far my favorite. Better graphics, faster battle cycles, new music, an expanded 'Dex, the Distortion World...I could go on and on.
hhaha, so far everybody has said Platinum except for 4 people who said Diamond and 3 for Perl.
I'm Voting Diamond. Even though Platinum version is better.