Interesting answers, I also did wanted you to post the games as xD. My own response to this would be the games with better exclusives in other words (Sapphire, FireRed, Diamond, HeartGold and Black) version. I mainly obtain the US releases depending on which games have better exclusives than the opposing game regardless of what the box would look like. When HeartGold and Black were released in the states I picked them up first before the other version. Although Black 2 and White 2 will be the sequel games, I do think I will be picking up my Black 2 game first because of the exclusives. Although the exclusives may be different I do in fact doubt it, due to exclusives from past games were logically the same.
Red (Ekans,Oddish, Mankey, Growlithe, Scyther, Electabuzz)
Blue (Sanshrew, Vulpix, Meowth, Bellsprout, Magmar, Pinsir)
FireRed (Ekans, Oddish, Psyduck, Growlithe, Shellder, Electabuzz, Scyther)
LeafGreen (Sanshrew, Vulpix, Bellsprout, Slowpoke, Staryu, Magmar, Pinsir)
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Gold (Mankey, Growlithe, Spinarak, Gligar, Teddiursa, Mantine)
Silver (Vulpix, Meowth, Ledyba, Delibird, Skarmory, Phanpy )
HeartGold (Mankey, Growlithe, Spinarak, Gligar, Manine, Phanpy)
SoulSilver (Vulpix, Meowth, Ledyba, Teddiursa, Delibird, Skarmory)
the names I colored black represent the exclusives which haven't really changed all that much, if you think about it. I did not include family members like Slowpoke,Slowbro,Slowking so just their basic form is what you really need to see here from my point of view.