Soundwave on 12 April 2015
They need to have 2-3 strong titles in the launch window and MUST have 1-2 big games in the post-launch window (this is now just as important).
1 game doesn't cut it anymore.
So this would be a good launch ...
Super Mario Galaxy 3 (launch day)
F-Zero NX (smaller scale title)
Animal Crossing (1 month after launch)
Luigi's Mansion 3 (2 months after launch)
Mario Kart 9 (4-6 months after launch)
That is a good launch. Then bring in Pokemon as the 2nd holiday title when you have some install base.
Having one big-ish game at launch and then nothing for the next 2-3 months ... not a good launch.
