Everything points towards a mobile centric ecosystem that's about lowering the barrier of entry with low cost hardware and games adopting different kinds of business models. There will be your Zelda and Monster Hunter too, don't worry.
I don't think NX has a new gimmick related to the way you interact with the system, instead the focus will revolve around the word social and sharing, as in, sharing your experience with others either by directly playing with/against them, uploading a MK8 video to youtube that captured a cool sequence, sharing a funny moment in Tomodachi Life, or let others enjoy your creations in games with level editors (which are common nowadays; Mario Maker, Pushmo World, Tipping Stars)
In terms of external software support, Nintendo just received a port of Minecraft and they are rumored to be the first system to see a port of Undertale, these are two examples of games that appeal to Nintendo's existing userbase. If you spend time browsing Miiverse you should be aware of that. Basically family-friendly games like Scribblenauts are a good fit for Nintendo's ecosystem.