New permission factions.powerboost which is required to use the above command. This permission is added to the factions.kit.mod permission kit.
example usage:
/f powerboost p Player1 1.5 (give player "Player1" a bonus of 1.5 power)
/f powerboost f SomeFaction -6 (give faction "SomeFaction" a penalty of -6 power)
Vault: http://dev.bukkit.org/server-mods/vault/
Note: for proper faction bank support in iCo5 and EssentialsEco, I recommend waiting for Vault 1.2.5 to be released which addresses faction account creation issues.