I honestly think Nintendo will not be able to retain the crown next gen in terms of home consoles. Let's be honest, the main reason the Wii was such a hit was because the motion controls appealed to many who normally weren't that into gaming. But next gen, all 3 will have motion controls from the get go, so no playing catch up there. In terms of graphics, the next Wii I expect to be slightly better than the PS3, but that means that the 360 and PS3 will still be able to compete with it for the year or so til their successors come out. And when they release, their graphics will be like the next-gen Unreal presentation from a month or so ago, which will blow away the Wii2 by comparison.
The only thing that I see Nintendo has gained from this is maybe around a year head start, but as many consoles have shown before, that doesn't always work out in your favor. While it may force MS to try and come out with the Next Xbox around the same time as the Wii2, I think Sony will stay with what they probably were already shooting for, a 2013 release for the PS4.
