I like the new scouting AI. When a creature is marked as a scout, he will run back to his buddies to report any enemies he sees before he attacks. So this means you may be walking down a hallway and see a goblin, who immediately turns and runs through a door, and seconds later, a goblin war party comes boiling out of the doorway.

Scouting is cool because it's realistic (the goblin goes for reinforcements rather than take on the five PCs himself), and because it makes strategies besides hack and slash more viable. If your rogue can sneak up on the goblin and take him out, or your cleric can hold him, or your wizard can zap him before he gets through the door, then you can avoid fighting the war party altogether.​