Yea i expect SMP to be pretty big as it is the first big family party game for the Switch. It will drive the family market for the holiday season while pokemon drive the casual market and Smash the core more mature one.
They have a really nice second half for everybody. Between these and other games getting announced like Diablo 3/Warframe etc Switch will be everywhere online and in the shopping carts.
Also, im impressed at MP4. I know it will be a big success and for SURE the best selling Metroid game. If its not a disaster, i can see it surpassing 5 millions lifetime. Franchises outside of Mario are getting way much exposure with internet now. Even Zelda was unknown by still so many and there it is now with Botw still in the best selling games after over a year.
Switch being their only system = more time and budget on games = more quality and ambitious titles = better press = better sales.
Switch is the best thing they could do and will be such a golden era, we only started and have so many great memorable games already.