Smashchu2 on 02 February 2011
Nintendo wil announce one when they think the competition will (Sony). The 3DS is a testement to that. They show it off at E3, and Sony reveals the NPG in January of this year. Nintendo knows it will be death if they release it late. Expect it in 2012 to 2014, which is a resonable window for when competion may enter.
Nintendo will not do it as a result of laging sales. Nintendo's strategy is release game, and they have mentioned it everytime they talk about their Wii sales. This year is the year where they will have the software ready to try and start growth (stallled do to the 2 year development cycle of games).
