I don't know why anyone is surprised at what is going on here.
Sure, Uncharted 4 slipping into next year was shocking, but the other delays were not. Every single year developers cram a bunch of really excitable titles in only to get cold feet and push it back. Not only to allow more dev time, but also to give space to breath from the Uber Sellers such as COD and Star Wars Battlefront this year.
Everyone seems to be forgetting that Sony still has the larger selection of games, and the highest rated ones to boot. Its not like once the year is up all previous games created stop existing. We got 2 Huge AAA Exclusive games in the first few months of the year which is very unusual. One was a flop, but Bloodborne is still the highest rated original next gen exclusive.
Sony's rest of the year is full of a lot of padding titles sure........but so is Microsoft's. Gears Remaster and the like. If not for Halo 5, everyone would be thinking the same of their lineup as they do Sony's. Many have become hesitant about Halo 5 after the colossal failure that was MCC, so who knows how well it really will do. Halo 5 will sell gangbusters, but I doubt it will turn the tide of this Console War and Sony knows this.
As far as E3 is concerned: I highly doubt MS will have any surprises for this year although this is probably their best output from 1st Party since they got in the game. Gears:Re, Halo, Forza, Fable Legends, Crackdown gives them a strong 1st party appearance, while their Tomb Raider will give their 3rd party credence strength. Yet mind you, MS had NOTHING for the first part of the year.
Sony already gave us Bloodborne and The Order early this year. E3 will show Until Dawn(I imagine a Halloween release), Tearaway Unfolded, God of War. We will still get footage of Uncharted 4 for next year. I still feel there is a very strong chance of Gran Turismo being revealed for this year. Sony has such a huge stable of 1st party game studios we just don't know what they will pull out of the hat. 3rd Party wise, Sony has No Man's Sky, Persona 5....... which is pretty much game over for everything else anyway :P
And then there is the 3rd Party Multiplatform camp. Jusus, there is a LOT going on there that we will barely have time for, and you all are wondering why games are getting pushed? We have the lure that Fallout 4 might actually be dropping this year. We already have MGS5, COD:BO3, SW:BF, Assassin's Creed: Syndicate, Mad Max, Rainbow Six, The Witcher 3 in a few days, Lego Jurassic World, Lego Dimensions, Infinity 3.0, Possibly Skylanders WOW edition, Rockband 4, Guitar Hero Live.
Now seriously think about these games above. Everyone of them is pretty huge. So less games on all fronts would be a blessing. I don't think the Holiday can survive as is and some of these games will have to bite the bullet and delay.