Pearl, because I already have the Japanese Diamond version~
It doesn't actually matter which game you get; they're pretty much the same game, only with version exclusive Pokémon.
But, to be honest, i'd get Diamond first, for Dialga.
But i'd end up with both ANYWAY....
LadyCharizard
I'm getting pearl. I've heard that everyone's after Diamond so I want an edge when trading.
I am getting Pearl, it's a flip side because I like more of the exclusives on there and also as PokeLord2 said, you'll get more people wanting to trade with you since you have the 'rarer' Pokémon.
I'm getting US Diamond, not because I really want to, but I've Japanese Pearl with me, and my friend's getting US Pearl anyway >.>;
Pearl because everyone will want the pokemon for it xD
I preordered Diamond and my friend is getting Pearl, so I'm set.
I will get Pokemon Diamond because I like its legendary and his exclusives.