"Hey.. this game is dominated by the competition for vision.. let's not let them buy wards!"
whoever made this decision should be fired immediately.

Have you even tried imagined what this new map would be like with wards? It would most likely take only two wards to cover a majority of the jungle, leaving only the long path from the top-lane base entrance uncovered and some of the (stupidly thought-out) speed pad uncovered. Then one more once Vilemaw spawns. At least the Teemo / Nidalee / Shaco faux-wards only help protect single paths.

The only way I could see bringing wards to this map is to significantly reduce their sight radius on it. I think the vision items serve this purpose just fine, though - they only work for 10 seconds, and once every minute, but this is all you need to make sure the path you are about to take in the jungle is clear, or to make sure extending is safe for the moment.

They need to add wards, heck make them last maybe 1:30 or have them be visible.