features.txt

commercially viable because of only GPL-compatible code
inis are much easier to distribute as "defaults" as they don't vary as much by platform (not that I endorse doing this)
keyconf now handles cheat codes
has a cooler icon than zdoom
GAMEINFO now has a ticrate property
more sane key and cvar defaults
the best sounds and placeholder graphics for any zdoom.pk3 ever distributed by terminusest13
cl_morphbob to allow player sprites to bob while morphed
cl_facekiller enables/disables facing the thing that killed you
cvarinfo now has an "acsonly" flag
subtractive glowing flats in GLDEFS, via FLATSUB and friends

decorate:
A_GiveScoreToTarget([int score = (actor's Score property)])
Score actor property as the default of A_GiveScoreToTarget, will probably change this a bit later
+PLAYER.NOFALLDEATH flag that makes the player view not fall to the ground when they die
A_PlaySound can now pitch shift
+ROLLSPRITE allows roll to be applied to actors that use sprites
const expressions added
A_UserPSprite([int layer = 1[, state pspState = ""]]) allows you to overlay sprites like a flash state, but with 16 slots
A_ClearUserPSprite([int layer = 1])
the tracer of a healer (ie archvile) is set to the thing it's healing, and vice versa
NoHeal "actor"[, inherited] actor property will disallow this actor from being resurrected by the actor, if inherited is 1 it will also check for things that inherit from that actor

acs:
ChangeFlag function
GetTicrate function
GetActorFloorTexture/GetActorCeilingTexture functions
SetPlayerBobMul/GetPlayerBobMul functions
PickActor's last argument is now a bitflag (PAF_FORCETID / PAF_RETURNTID)
PlaySound can now pitch shift
APROP_MaxStepHeight / APROP_MaxDropOffHeight
GetGameProperty/SetGameProperty allow you to disable/enable saving and disable/enable respawning
LineAttack has an optional pufftid parameter
Warp function to mimick A_Warp
SetInputLock / GetInputLock will lock input for the following
INPUT scripts to handle all key input while it is locked
acc now allows scripts like this (it was an oversight): script 1 (str a, bool b, int c)
KeyIsBoundSym function to get if a key is bound to a symbol (for INPUT scripts)
ReadUserData allows you to read arbitrary files from a userdata namespace (UD_START/UD_END or in a pk3 userdata/)
ReadUserDataChar does the same thing but with a single character