New PvP Talent: Shadowfall – Gain the Nightfall talent with 100% increased chance to cause your next Shadow Bolt to be instant. If you already have this talent, you may select another in the same row.
Its interesting and seems to be meant to play off the 4 set that gives you an occasional free and instant Malefic with shadowbolts, but that seems like a design space waste as you'll still not be actually using your soul shards. That meaningful increase to spread pressure is a fun direction, however.
Still sad they don't give Affliction Warlocks a weaker instant shard spender. Its so annoying to be stuck on five shards until Rapid Contagion comes off cd. Making Rapid Contagion only last something like 5 seconds, only cost one shard, and having Malefic be stronger in pvp so its actually better to cast can make using shard an intelligent choice dependent on whether you can fake casts and dodge kicks, and thus be as fun as it was in Legion or MoP days.