The upcoming RPG, ASH, will be the first DS game to run off a 2 gigabit (256 MB) card. This is a big jump from the current standard of 1 gigabit (128 MB).
If this becomes standard for future DS games (and with the constantly decreasing cost of memory, it likely will), it could lead to larger DS games with more features (more voice overs, cutscenes, content, better graphical polish perhaps).
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