Spotting enemies was a huge gameplay mechanic in Battlefield: Bad Company 2's multiplayer, allowing you to place a marker over an enemy in the distance for your entire team to see. Spotting was also quite broken, because a marked enemy would remain marked even if hidden from sight. That's all changed in Battlefield 3, where a marked enemy will lose the hovering red-tag when they retreat back into vegetation or any other form of concealment. Said spotted enemy will still appear on the mini-map, though.
Those pesky new jets, however, will always be marked. Makes sense, because, they're, um, huge.
[Battlefield3Blog]
