Nintendo has a few problems, but the main one is actually evident right in the title of this thread. It's their marketing.
I was wondering why nobody brought this up, but Digitalfoundry FINALLY did.
If Nintendo would have introduced the Switch as a successor to the 3DS that can also dock as a home console rather than a home console first that can be portable it would probably be looked upon differently. But I believe that Nintendo being as conservative as they are did not want to risk disappointing the handheld market with a product that has so far received mixed initial reaction. Nintendo can try to dodge or deny this all they want, but if you look at the timeline it is obvious that this is really a successor to their mobile platform rather than anything else. They just wanted to be safe about it.
This gives them an OUT and then introduce a "true successor" to the 3DS if this bombs. Even though I think most hardcore who follow this industry closely know that this is probably the route Nintendo wants to take to satisfy both the home and portable crowd forever.
With all that said I think the Switch will be fine for a few reasons:
The 3DS is old...the people who play on portables are ready to move on to something new after 6 years on the market. The release date is not a coincidence, Nintendo is stubborn and quite predictable.
GBA - March 2001 release
The DS line was their main portable for just over 6 years
3DS - March 2011 release
Switch - March 2017 release
The ports will be coming. Mario Maker (The full version, not that gimped BS 3DS version) will be incredible if Nintendo gets their head out of their asses and FINALLY figure out a COMPETENT online system. I don't even expect a GOOD online system, just COMPETENT is all we ask for.
If they can convince EA/2K to release just a SINGLE version of Madden, 2K and FIFA the system will be GOLD for people who have been dying to play sports games on the go. I am one of them, I held onto the vita for so long just because of MLB The Show.