It has a 0.5 second cast time.
Can be used on druids in flight form.
Can only be used on unfriendly players.
In Warlords of Draenor, this item will be added to the new Toy Box feature and no longer take up a bag slot. You will be able to "use" the item straight from the Toy Box interface.
The Toy Box will be account-wide and therefore so will this item.