Here are some of the points I took from the presentation and surrounding hands-on footage - both good and bad.
Experimental Mario is back
It's been pointed out that Super Mario Odyssey is the spiritual successor to Super Mario 64 and Super Mario Sunshine - the only two truly open 3D adventures in the franchise to date.
E3 2017 confirmed that this was the case - and then some - with Nintendo expanding on Odyssey's open world flavour. This is going to be the biggest, most freewheeling Mario yet.
But to me the more exciting news is that the crazy, experimental strain of Mario is back from Super Mario Galaxy and its sequel. Given that these two Wii games are arguably my favourite two 3D iterations of the series, I'm more than a little excited.
For example, the ability to throw your sentient hat onto enemies and objects and possess them, taking advantage of their unique abilities, looks set to be deeply empowering. It reminded me of the crazy debug mode cheats you used to get in the old Sonic games.
Metroid Prime 4 confirmed
It was the rumour many of us didn't dare to believe - not because development of Metroid Prime 4 was completely outside the realms of possibility, but because the pain of another Nintendo generation neglecting the Metroid franchise was too much to comprehend.
If you never had a Game Cube, or you missed out on Metroid Prime: Trilogy on the Wii, then you should know that this sub-series is right up there with Nintendo's best.
The original Metroid Prime, in particular, is to Super Metroid what Super Mario 64 is to Super Mario World and Ocarina of Time is to Link to the Past - a near-perfect 3D realisation of a series that was conceived in 2D.
Mario + Rabbids = exciting (who knew?)
If in the years to come I ever come to doubt Nintendo's uncanny powers of alchemy, someone needs to remind me of this year's E3 showing. After all, this was when I was heard to utter the words: "I'm really looking forward to playing that new Rabbids game".
In terms of unlikely sentiments, this is right up with me saying "I really fancy a bowl of brussel sprouts" or "I can't wait for the new Coldplay album". Never gonna happen.
That I did indeed say that initial sentence (more or less) I can only attribute to a hefty sprinkling of Nintendo magic. Suddenly, Mario leading a bunch of gallic Minion wannabes through a game of primary-hued XCOM seems like the most natural idea in the world.
Strange times we're living in, folks. Strange times.
New Donk City is just plain weird
So Mario is getting his freak on for his latest 3D adventure. As I've already discussed, this is a good thing after a generation of overly safe (if impeccably made) 3D adventures.
But the main level that's being used to show off the game, New Donk City, just seems plain weird. And not in a good way.
For some reason, Nintendo has chosen to render this take on The Big Apple in a pseudo realistic style. This really jars with Mario's fantastical elements. It also looks dated from the off, and will almost certainly age badly.
Metroid Prime 4 is a long way off
Metroid Prime 4's announcement was a joyous moment, but at the risk of sounding like an ungrateful brat (too late?), I wanted more. I wanted to see footage. Perhaps nothing more than a pre-rendered intro that hints at the direction Nintendo is taking here.
Heck, even some pre-production artwork would have been better than what we got - a brief, floating icon. Teasers are all well and good, but we can all decode what this means: Metroid Prime 4 is nowhere near release.
In fact, given the way in which Nintendo handled its Kirby and Yoshi reveals (a vague 2018 release date alongside a decent amount of gameplay footage), I'd suggest that Metroid Prime 4 won't be hitting the Switch until 2019 at the earliest.
Which brings me to my last downer...
2017 Switch roster is looking slender
From the off, Nintendo has seemed keen to fill the Switch release roster with a steady drip of new games. However, 2017 is looking slightly threadbare.
What did Switch owners have to look forward to for the rest of 2017 prior to E3? There's ARMS out later this week (so technically it's a first half 2017 release), Splatoon 2 next month, and Super Mario Odyssey in October.
I'm not counting Skyrim, as it's a conversion of a six-year-old game. Fire Emblem Warriors is fine if you like that sort of thing, but is hardly a major release to excite the masses.
All that Nintendo's E3 added of note to that list was Mario + Rabbids Kingdom Battle, which was a pleasant surprise, but hardly a blockbuster. Xenoblade Chronicles 2 will be a big game for JRPG fans, but that's a pretty niche audience these days.
The Switch is brilliant, and there are brilliant games coming out for it. But the second half of 2017 in particular is looking a tiny bit undernourished. Or is that just me?