These lists are always a wait and see type deal. Some wont make it and others will be added for sure, and you never know which ones will end up actually being good (subjective I know). That said games on my radar are-
PS4 -24
Alienation
The Tomorrow Children
Until Dawn
The Order: 1886 (beat it and liked it, flawed but beautiful)
Bloodborne (beat it and loved it)
Deep Down
Rime (most anticipated PS4 exclusive if out this year)
Broforce
The Vanishing of Ethan Carter
Axiom Verge (beat it and loved it)
Chasm
Ether One
SOMA
The Forest
The Hum: Abudctions
The Talos Principle
Enter the Gungeon
Hellblade
The Witness
No Man's Sky
God of War III Remastered (beat it- ready to go round 2 with hd version)
Journey (beat it- ready to go round 2 with hd ersion)
Tearaway Unfolded
Everybody's Gone to the Rapture
X1 -5
Halo 5: Guardians
Cuphead
Ori and the Blind Forest (so far only X1 exclusive this year on my must play list)
Rise of the Tomb Raider (loved re-boot, X1 timed exclusive most looking forward to)
Inside
IMO PS4 'wins' this list war based on depth and breath of software (both my personal tastes and just in general based on sheer volume of content). X1 arguably has the stronger holiday AAA stuff (even if just from a marketing perspective), but the never ending flow of diverse content is what keeps my PS4 on all year, while my X1 library feels a bit sparse and can thus stay loaned to my brother in law until tomb raider's out.