It's literally just the new "silence." You can use it to stop spells, like scylla/xande nukes during WoD, or the paralyze during Qarn, etc. Its functionality hasn't changed at all. It used to say "inflicts silence for one second," now it says "interrupts." Both ranged and tanks already had these abilities, they already had their place, it's just been highlighted so people stop screwing it up/ignoring it.