Looking at wowhead's action bar simulator,
we aren't getting a single new ability that isn't a direct replacement of something they're removing:
http://legion.wowhead.com/action-bars#AAbxcBAQUAAAAA
Recuperate --> Crimson Vial
Shuriken Toss (now baseline, but Smokebomb moved to talents and MfD and DFA both moved to the same talent tier so you can only select one of them)
Backstab --> Gloomblade (if talented)
Ambush --> Shadowstrike
Rupture --> Nightblade
Fan of Knives --> Shuriken Storm
Subtlety isn't getting a single new ability that isn't a direct replacement of something they're pruning.
On top of this, many abilities are being pruned without replacement:
Shadowstep (used to be the spec-defining 41 point talent in the subtlety tree, now an Assassination exclusive)
Hemorrhage (used to be a 21 point talent in the subtlety tree in Vanilla, now an Assassination exclusive)
Slice and Dice (had it since Vanilla)
Premeditation (was the 31 point subtlety talent in Vanilla)
Shadow Dance (introduced in WotLK and came to define the spec as the 51 point Subtlety talent)
Gouge (had it since Vanilla)
Blind (had it since Vanilla)
Garrote (had it since Vanilla)
Preparation (had it since Vanilla)
Shiv (had it since TBC)
Crippling Poison (had it since Vanilla)
Wound Poison (had it since Vanilla)