GameSpot (and GameFaqs) have just added two new pages under their DS section. Those games are Digimon World: Dawn and Digimon World: Dusk. These games are the English versions of Digimon Story Sunburst & Moonlight (as you can tell by the URLs).
This is most likely their names, just keep in mind that this is no official announcement, it is just a new page on GameSpot. Maybe if Agumon waves his tail enough, we will get the game soon.