Nintendo does not need a graphical successor to the U

[Soundwave]

Even if Nintendo made a portable which could double as a home console or had a home console dock that allowed for games to play be played on the go and at home I don't think that neccessarily means all of Nintendo's eggs are in one basket.

I hear that a lot, but there's really nothing stopping Nintendo from making a different type of hardware platform to compliment that later on.

The home/console hybrid could appeal more to the traditional audience that Nintendo targets (kids, families, Japanese households), and they could always 1-2 years later bring out a console made more for Western tastes that would be far more powerful for example.