Lonely Zones

For me, one of the most jarring feelings in a mmorpg is being in a location that has been set-dressed to be desolate and yet is jam-packed with players. It's not much better to be alone in a place that should be full of players.

Developers and designers have spent time and effort devising ways to encourage players to distribute themselves in a way that complements the settings. But I can't think of much that has been done to make zones themselves respond to population levels.