Not really sure what to look forward to on my PS4. Earlier this year I was enjoying the hell out of RE7 and Nioh; Yakuza Zero was also fun, albeit repetitious after a while. I picked up Nier Automata but haven't played it yet since I'm still playing Zelda (210+ hours and counting!). Not sure what there is to look forward to on that front the rest of the year, so E3 will be important for Sony.
But yeah, this year it's all about Nintendo. I expect their E3 will give a major push for ARMS (which simply looks fantastic, and is super-addictive according to those who played it) and Splatoon 2. We'll see more of Super Mario Odyssey probably the only game that will compete with Zelda for the highest meta-critic score this year and Xenoblade Chronicles 2, a.k.a. sequel to one of the best JRPGs ever. Oh, and we'll see Fire Emblem Warriors, from the people who made the superb Hyrule Warriors.
I think it's highly likely that the rumored Pokemon Stars and Super Smash Bros for Nintendo Switch are also real. Those would be two killer holiday titles right there. The Mario Rabbids game is also likely real (in a Ubisoft video declaring support for Switch, there were Rabbids statues dressed as Mario characters in the background!), and I'm eager to see it.
My question is, are we expecting a Pikmin 4? People seem divided on whether the Pikmin game Miyamoto mentioned nearing completion is Pikmin 3DS (now called Hey! Pikmin) or a mainline Pikmin game. Also, according to the thread here on Nintendo's first-party studios, the Animal Crossing team is working on "Animal Crossing projects" (how vague!), so I'm guessing a Switch title is in the cards and might be ready to show.
Maybe they'll also show the DLC for Zelda. Probably not the story DLC that's coming later in the year around GotY voting season, but at least the first round of DLC with the hard mode, Cave of Trials, etc. Also a chance for them to showcase the in-game functionality for the three new Zelda amiibo. I can see them plugging those on Treehouse Live.
Treehouse Live is easily the best E3 coverage around. Looking forward to it. Also hoping there will be another pre-E3 event like the Smash Invitational or Nintendo World Championship. Imagine if they did another NWC focused on the Switch, with Zelda "any %" speed runs, battles in Mario Kart Deluxe, 2v2 in ARMS, Turf Wars in Splatoon 2, etc.
It's gonna be good.