Ever tried to smack someone in the face with a SMG and get the short end of the exchange? That opposing player was probably hosting. It’s been a problem since Halo 2, and no one at Bungie apparently thought it was worth addressing until now.
With the latest auto update, melee kills are now equal ground. It should be immediately apparent with your first match. If both players are injured enough, the dual melee with kill both players flat. The overall feel is different, and while it’s hard to describe, the B button enabled attack now feels smoother. The timing is also radically different, requiring an earlier start if you want to come out ahead.
Various other tweaks are part of the patch, and are detailed by Bungie. Also, if you ever wondered how the game manages to figure out who lives and dies, they offer a well rounded FAQ on damage assessment in that same post towards the bottom. If you’re nerdy enough, know that an assault rifle bullet does 7.5 points of damage to an enemy. Pull that one out next time you’re being taunted and see how cool you look.