Wow - that Neogaf list makes me realize how many good DS games I haven't got yet.
Elite Beat Agents was also missing from my list - its an absolute "must buy" IMO.
And for a rare treat, with unique gameplay, challenging game, long adventure - and a twisted view on capitalism (and the world in general) - you can't go past "Tingles Rosy Rupeeland". Of all the DS games I have finished, this would have to be the most "rare". Its definitely worth it, in terms of "a study of unique game play" alone (solid 8-8.5/10 IMO).
Get Final Fantasy XII : Revenant Wings if you don't have it; it's one of the best DS games I've played (and I own more than 40) and a refreshing FF experience in its own right even a bit flawed in its RTS core.
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