User blog comment:Emptylord/Custom Champion - Charlette the Oncoming Swarm/@comment-220.239.246.116-20121016103936/@comment-220.239.246.116-20121016205241

Yes, but unlike wards, these do not cost money, and can be placed every 30 seconds.

the cairvoyance spell was nerfed for giving much too much map awareness and controll, and it still had a hefty cooldown. but now that i know the cooldown is 30 seconds it isnt as bad as i had first imagined and dont believe it to be OP. also, with your above question, to balance out having 5 active wards anywhere, i believe they should still only give sight when you are on the webbing, it would lead to some interesting gameplay.