The new Season 3 item Twin Shadows has the following active:
Unique Active: Hunt - Summons 2 invulnerable ghosts for 6 seconds to seek the two nearest enemy champions. If they touch an enemy champion, they slow his movement speed by 40% and reveal him for 2.5 seconds. 120 second cooldown.
I just tried it in a game, and it revealed a Garen who was hiding in some brush, previously out of my vision. The active states that it seeks the two nearest enemy champions, revealing them on contact. Does this include stealthed champions?