Guerrilla’s new IP has been in development since 2010, this one had been rumored to be a Fall 2015 release, before Uncharted was penciled in for that slot, with Uncharted moved to Spring Guerrilla’s sci-fi, open world action RPG Horizon will very likely stomp all comers this holiday!
The likes of TLG, Eight Days and The Getaway were never canceled, most likely placed on hold until PS4 had a substantial install base, which is the case now.

Obviously Naughty Dog will likely have new Uncharted 4 footage, PSX was amazing and it’s been 6 months since that demo was put out.
GT7 is probably well underway, another likely candidate for a 2015 release, especially with the 20th anniversary happening in 2018, most GT games have come earlier, rather than later, with around a 2 year gap between releases.

Media Molecule & Sony Bend also have new IPs in the works.
London could still be working on Eight Days and The Getaway, only for PS4 now.
TLG, maybe a new Gravity Rush but for PS4.

Besides Horizon Guerrilla also has at least one other title in development, potentially a new Killzone or a Resistance game, which is likely being handled by the awesome Guerrilla Cambridge studio.

Add in Level 5’s *bigger than White Knight Chronicles” title, Quantic Dream’s new IP (another game years in the making since before 2013).
So many big games could be ready to show.

Not to forget the brand new re imagined Ratchet & Clank, probably
visually on par with the movie’s awesome look, that will likely get it’s
debut at E3, with a Fall release date.

With Kaz’s recent comments on making huge investments in Playstation 1st party and new projects this will likely just be the tip of the iceberg for Sony’s development might.

E3, along with Gamescom, TGS and PSX are all gonna be phenomenal for Sony.
Very exciting times for gaming.