HappySqurriel on 15 July 2008
Recently (I believe it was TGS 2007 IIRC) Nintendo stated that they felt that they didn't want to continue announcing games (and release a lot of information) years in advance, and they wanted to wait until games were closer to release ... Since then Nintendo has (practically) had surprise releases of games by announcing a game would be released only a couple of months before it was released (see: Mario Kart).
It's hard to say why they choose this strategy, but I suspect it allows them to focus their marketing efforts towards games that are currently in the pipeline (and therefore receive higher sales) than to focus on games that may not be released for several years.
