Nintendo's social network is coming to the 3DS, mobile devices, and PCs, but a little later.
Nintendo's recently announced Miiverse functionality will also be coming to the 3DS, future Nintendo platforms, and web-connected mobile devices and PCs. However, when he announced these plans at the recent Pre-E3 2012 Nintendo Direct event, Iwata said that this would not happen at "launch."
Please read our previous article covering the same event for more details of the Miiverse social network that will be an integral feature of Nintendo's upcoming Wii U console.
Nintendo's talked about making their services available through PCs before, but those comments referred to allowing people to purchase downloadable games on a computer instead of only on their console.