This thing will be a godsend to casual gamers, or even hardcore folks with alts who never get played for attunement. Basically (I think it's a one-per-kill drop, though maybe it's less than that), Vashj after 2.1 will drop a scroll (with one use, I believe) that can attune anyone level 70 to Serpentshrine Cavern. So all your guild has to really do now is attune 25 people and down Vashj, and then she'll drop scrolls which will let other folks in. All of the raiding fun, without any of the attunement quest (which ran from Heroic Slave Pens through Gruul and Karazhan).
In other Vashj attunement news, Boubouille is also reporting that unlimited Vials of Eternity are dropping-- one for every person in the raid. That's needed for the Mount Hyjal attunement quest, and before, only a few dropped at a time. So a couple of good changes for casual raiders-- looks like the road to Mount Hyjal is a little less steep than it used to be.