Actually the DS2 is already in exsistance, Nintendo sent one to the Pokemon company so they can take the DS2's features into account for the the 5th Gen, I guess because they're looking at the new games to really expand the DS2's features since Diamond and Pearl didn't use the DS/LiteDSi's features until HeartGold and Soul Silver.
So really the only people who have a clue about the DS2's look/features are the people who made it and the Pokemon company
In case your wondering wtf I'm talking about:
Diamond, Pearl and Platinum used the bottom screen for very few features, it only applied to the Poketec and the battle menu.
HeartGold and SoulSilver however used the bottom screen and used it a lot more then DPPt, considering you used the stylus screen for ALL the menus (Accesing PC, Bag, Battle Menu, etc)

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