I voted E3 2010.

Donkey Kong Country Returns, Goldeneye 007, Kirby's Epic Yarn, and Zelda Skyward Sword revealed, plus a spectacular unveiling for the 3DS.

2014 was bomb.

Edit: Misread post

Toss up between 2006/2010/2014. I can't decide between those.

• '07 was average. 
• '08....let's not go there.
• '09 had good games but it felt too relaxed and laid back. Not enough hype. 
• '11 would have been better if they didn't confuse people with the Wii U anouncement.
• '12.........Before E3 2012 I thought it was impossible to kill the buzz of a new console.
• 'Most of the megabombs shown during the 13 direct were already known. 
• '15 wasn't better than '14. 

I don't mind if we already knew about those games, plus... if you think this way, you shouldn'd include Zelda, Hyrule Warriors and XCX on your list... since we already knew they were coming (and already have seen XCX and HW in motion by that time). Regarding Star Fox, we just learned it was in development, but not a single pic was released.

I just think Mario Kart + Smash Bros + Donkey Kong + 3D Mario were more impacting and made a better show filled with a bigger number of important games for us. It also had the usual stuff we like (XCX, WWHD, Pikmin 3, full blowout of Pokémon X/Y, etc.).

Nothing beats 2008 ton of gems shown off that year. 2015 is a close 2nd

E3 2006 was great because it really hyped the Wii and people caught on on how it works, especially with games like Twilight Princess, Wii Sports, Metroid Prime 3, and Super Mario Galaxy.

E3 2010 was another gem with Skyward Sword (despite the technical issues due to outside interference), Donkey Kong Country Returns, Kirby's Epic Yarn, Goldeneye 007, Epic Mickey, NBA Jam, and the unveiling of the 3DS and the revival of Kid Icarus.

E3 2014 was great as well, even though we knew a pretty good amount of the games already. It was the execution, I believe, that really took the cake. Bayonetta 1 and 2 in one package? Zelda Wii U teaser. The tease of the return of Star Fox. Palutena, Mii Fighters, and Pac-Man in Smash? The Smash Tournament was hype (especially Mega Man's final smash) and the Treehouse event was unique, showing consumers 3 days of straight-up gameplay. Of course, I cannot forget Splatoon, Xenoblade X, Yoshi, and Super Mario Maker, which were great highlights this year.

I would also like to add E3 2013. If people complain that we've already heard about the games unveiled during that presentation, then we could say the same thing for 2014 outside of Splatoon, Kirby, and Mario Maker. 3D World and Tropical Freeze ended up being two of the best platformers so far in this generation. Great seeing more footage of Pokemon X and Y. Finally, ending the presentation with the game that created hype before, during, and even over two years after it's initial unveiling, Super Smash Bros. I mean, who would've thought Mega Man would've made it after years of being left behind by Capcom? I still cannot stop replaying some of the reactions to this particular trailer of Smash.

I have only watched the 2014 and 2015 E3 Digital presentations so I will pick 2014 ;)

Sad people are voteing 2014... wasnt that great.
Last fantastic one Nintendo had was 2006.

And thats still nothing compaired to the Wii reveal, and the games it had at E3 in 2006.'

(mario galaxy, zelda, ff crystal chronicles, madden, rayman,... and tons of NDS games)

The last great E3 nintendo had was 2006.