Well after the first two days Nintendo had the best conference/event, then Microsoft, then Sony.
Exclusives, I guess that depends on one's own tastes, but I thought it was the same order.
Nintendo showed the most actual gameplay, but only teased two of the big games in Zelda and Starfox so far (apparently they will be revealing a few things every day, but Starfox was still too early in development graphics wise). A lot of cgi trailers shown by Sony and Microsoft, but Sony showed more actual gameplay in trailers between the two.
It was nice seeing more unique games and different art styles this year. Also cool to see Platinum have two (technically 3 with the Bayonetta 1 remake) and Suda 51 have one game shown, as well as Valhalla. A lot of crazy Japanese action there.
Three big game builder games with Mario Maker, Little Big Planet 3, and Project Spark.
Sunset Overdrive looks good.
Splatoon looks like a ton of fun.
Nintendo bringing out crazy art styles with yarn Yoshi, claymation Kirby, classic Disney Zelda, and Nickelodeon Splatoon.
RPG and Adventure game fans should be sated with Zelda, X, Fable Legends, Witcher 3, and Bloodborne.
Not enough horror games in the headlines yet, hoping to see more of the new Aliens game, hoping to see the new RE, The Evil Within, Fatal Frame WiiU, and a lot more.
Watched the Smash Bros. tournament which was very fun, wish my main character Kirby won.
Like this E3 a lot better than last year's.