I'll just copy paste what I said elsewhere about E3 so far and my hopes/expectations for Nintendo:
Microsoft didn't have anything "OHMERGAWD THATS AMAAAAAAZING" for me personally, but aside from the very beginning, they had no real low points in their conference and kept me mildly to moderately interested in each individual title, and the presentation and pacing was really well done.
Sony had a few big hitters for me like LBP3 (IT LOOKS SO ****ING HAPPY AND IT'S COMING IN A FEW MONTHS) and Uncharted 4 and Anzu, but some of it was remasters of very recent games that while I am excited for, don't show off anything new for the PS4, and the rest was mildly intriguing. Also, a lot of their stuff is not coming out until 2015. They also had a lot of third party stuff and focused way too much on stroking their ***** and Playstation Now and all that jazz in the middle of the conference, as well as the long segment about Powers (don't get me wrong - while it's the first I've heard of the graphic novel series, it sounds really interesting and deserving of a show - however, it's not a game, and that's what I came for). I was also expecting a revival of an old franchise, and I thought we were getting one with that one PS1 music game getting a name drop TWICE (I CANT REMEMBER THE NAME FOR SOME REASON IM SORRY), but nothing came of it. Also, a lot of the games began to bleed together much like Ubisoft's conference, because they were all gritty and **** and didn't show much actual gameplay, if any. They didn't present themselves as well as Microsoft either, and the pacing was kinda bad at points. The conference was definitely longer than it deserved to be.
For Nintendo, I am obviously going to enjoy all of the Smash Bros coverage, and they will win E3 no contest if they pull a UFC and release the 3DS version next week (I can dream). Zelda Wii U and Hyrule Warriors are also getting coverage, and we may see more from Yarn Yoshi and SMT x FE. We'll probably see a new Mario game, as Mario always has SOME sort of presence, but I don't think it will be Galaxy 3 (which should star Rosalina anyway IMO, if it does happen, similar to how Yoshi's Island was a subtitle for "Super Mario World 2" - just make it "Super Mario Galaxy 3: Rosalina's Story" or something - this would mean I could get my next gen Galaxy fix, my favourite Nintendo character/space waifu gets her own series, and the main Mario series could continue doing it's own thing) or a new 3D Mario platformer at all, as I doubt they already have something ready to show. Galaxy 2 was revealed two E3's after Galaxy 1, and HD/3DS dev time could be longer.
I also expect them to announce a DLC program for Mario Kart 8, and to have the first pack available today, for free. The other two companies had "It's out today!" announcements, so Nintendo could use one. And I am hoping for a revival of an unused franchise. We will also learn what the NFC stuff is all about, and Miyamoto's new IP is confirmed to be at the Treehouse stream. So yeah, I'm really pumped for Nintendo, they have a lot of potential.