Changes to Runes
The runes say: 3/5% chance to gain might for 20s when hit. (cooldown: 5s) which means it will trigger when you (or your pet if Ranger) receive a hit from an enemy. These runes can be changed completely, but in their current state and if their mechanics stay unchanged (so when you recieve a hit, the effect will trigger) this won’t affect Zerkers much, or PvE-content at all, since the encounters allow you to avoid most damage.
I highly doubt even if they made it a 100% chance to trigger it would have any effect on the PvE-community (where Zerker is currently the meta) since it’s not difficult for a 5-man group to stack up to 25 Might. (1 Firefield, 1-2 Blast-finishers per person every 24 seconds is not difficult at all) other Runes will most likely still be more favourable. The WvW/PvP-community how-ever it might effect in some way, but with all the incoming changes it’s almost impossible to predict.
Sigils do proc on hits you deliver, currently they proc on critical hits, which I believe they intent to change to a chance to proc on any hit, whether it’s a critical hit or not. This will make them more viable to people who don’t focus on Percision much. Which will make it easier to stack Might on yourself (unless you already had a 100% critical chance,) but I doubt the meta will take them over Sigil of Night (10% damage increase) or Sigil of Force (5% damage increase)