Safe first party bets for all three days mixed with hopes/dreams:
- BotW has a big presence on Treehouse stream and hands-on experience (deservedly) and has some significant new feature shown during the event itself. Not sure what to make of the launch date in Europe tho.
- 3D Super Mario Bros. will be as described by the leakers and will be available at launch. Open, adventure/exploration style Mario title with 2 player coop with a kind of tether being used to keep the players from getting too far apart (I imagine just like the existing kind of "bubble" system in 3DW that brings P2 back to P1). Coop will be a feature element and I wouldn't be surprised to see multiple playable characters (hoping they include the 3DW cast plus just a couple more).
- MK8+ is shown, out this summer. Some new content shown at the event, with more updates on new content from now until release.
- Spla2n is announced as a launch title. I guess the word is that this is more of an MK8+ situation so I guess we could call it that too. Basically I think it'll have enough new content to make the purchase more than worth it. Curious what they'll do for controls without the gamepad though.
- Maybe mention of the Mario x Rabbids RPG? Depends on if they position Ubisoft as a major partner at the show with BG&E2 and perhaps an Origins+Legends combo game? I think they'll make a good hoopla about Ubi support for Switch, so seeing the RPG wouldn't surprise me. Curious about launch timing for this.
- Pokémon Stars is briefly touched on as a thing that exists, maybe some footage just to show us how it's looking and then a "please look forward to more."
- New IP probably for launch day.
- Surprise "series revival."
- Super Smash Bros for Switch is announced last, showing two new characters: Ice Climbers and Rayman. Obviously this is a big ??? as to whether it'll even be at the event, but I have a feeling they recognize the strength of using this event to hype any new Smash content. If this appears tomorrow, I would expect full Smash-hype marketing to ensue until launch (Fall 2017).
Can't guess about third parties since they could very well just thumb their noses and say "we can't promise support until we know the success of the console." But I have a pretty good feeling Nintendo convinced a few of the bigger ones to be there at launch. I have a slight hunch DSTrilogy could be a thing announced tomorrow (I know what FS has said regarding this), plus there's Skyrim and sports titles. Honestly the third party support is the biggest unknown for me going in and it's also one of the most important things that need to go right.