I'll put all 1st party developers and then we can predict what they are developing.  Ill also be putting the ones we do know what they are working on

 

Sony

Studio - Project- My prediction

SCE Japan - The Last Guardian/Puppeteer - PS3 Release only

Polyphony Digital - Unkown -  GT6 Prologue PS4

Nuaghty Dog - Last of Us/Unkown - Uncharted 4 or New IP Trilogy PS4

SCE Santa Monica - Unkown - New IP PS4 Ealry 2014

Sucker Punch - InFamous Second Sun 

Guerilla Games - Killzone Shadow Fall/Unkown

Media Molecule - Tearaway/Unkown - New IP (3D world platformer)  or LBP 3D world Platformer

Evolution Studios - Driveclub

SCE London Studio - Unkown - New IP for PS Move and New Kinect like Camera

SCE Sandiego Studios - Unkown - New IP and MLB The Show

SCE Bend Studios - No prediction

Microsoft

343i - Unkown - Halo 2 Anniversary/Halo 5

Connected Experiences - Unkown - Helping Black Tusk Studios

Good Science Studio - Unkown - New Kinect IP

Kids & LIfestyle Entertainment - Next gen Fitness Game - No prediction

Microsoft Studios LA - Unkown -  Either an Action/Adventure, Interactive Movie (Or episodic)game, or a new show for Xbox Video

Microsoft Studios Mobile - Unkown -New IP (Puzzle Platformer)

Redmond Publishing - Working with multiple 3rd Party developers - No prediction

Platform Next Studios -Next Gen Core Title - No Prediction

Playful Learning - Next Gen Family Project - Party type game similar to Mario Party usign Avatars

Skybox Sports - Next Gen Sports game - No Prediction

Turn 10 Studios -Unkown - Forza 5 2014 release

Twisted Pixel Games - LocoCycle - no prediction

Xbox Live Productions - Unknown - New Kinect IP

Lionhead Studios - Unnanounced MMO IP - No Prediction

Rare Ltd - 3 titles being made - New IP Action/Adventure Jet Force Gemini, and New Kinect IP

Soho Prodictions - Unkown - New Kinect IP

BigPark - Unknown - Kinect Sports: Season 3 Possible hard bundles

Press Play -Unkown -No prediction

Black Tusk Studios - Next Big Game - New IP FPS or TPS.  Mix between Military and Scifi

Microsoft Studios Victoria - Unknown - New Core IP

Sentient Team - Working with internal and external teams - No prediction

Twisted Pixel Games are working on LocoCycle (http://www.ign.com/articles/2012/06/04/e3-2012-twisted-pixels-lococycle-announced)

SCE Japan Studio also works on Knack for PS4 and maybe Gravity Rush 2 for Vita (Project Siren)

SCE Bend Studio probably working on new Syphon Filter game for PSx or new Uncharted game for Vita (Killzone Mercenary is made by Guerrilla Cambridge)

Sony Bend isn't doing Killzone Mercenaries, Guerrilla Cambridge is.

Thanks and Gravity Rush 2 has been confirmed?

No, but the game director wants to make a sequel (http://www.computerandvideogames.com/369593/gravity-rush-2-hinted-by-director/)

Thats a good sign since the 1st one has a following now :) maybe it can turn into a popular series

SCE Bend Studios - Uncharted 2 vita (hopefully) Make it happen Sony.

Japan is also making puppeteer and rain. Santa Monica does the DLC for PSASBR and are also going to be working on DLC for GOW. Guerrilla also has a second team working on a new ip.

Press Play is making Max The Curse of Brotherhood (XBLA):

Oh wow that actually looks really good O.o Ive never even heard of it.  Looks like it will be using a combination of Kinect and controller.