How to get the changed Object in ember observer

I want to get the changed Object in Ember observer in view,

watchStatus: ( ->
    console.log "I want the changed Object here???"
    map = @get('map')
    trucks = @get('controller.model.content')
    i = 0
    while i < trucks.length
      @makeMarker trucks[i], map
    i++
).observes('controller.model.content.@each.status')