On Hardware side Sony to show off final VR and Neo SKUs and announce pricing and release date. Reckon both in time for Christmas. MS will announce an XB1 Elite, with some small HW changes, nothing on the scale of Neo.
SW side Ubi will "surprise" us with AC:Egypt, EA will triple down on the SW games from Hennig and Respawn as well as Battlefront WITH a campaign. Titanfall 2 will be shown, obviously since they said it is releasing in NOvember. More BF1 info and focus on MP, reckon they will surprise noone with news of XB1 timed exclusive content.
Believe we will see first gameplay footage of ME:Andromeda
Activision will be all CoD all the time.
I don't think this will happen, but I am hoping that Rockstar announce single player DLC for GTAV and RDR2. Won't happen because they don't care for SP DLC for GTAV and they won't be at E3
Ninty will have more than just Zelda, they have to. But I will be wrong on this