As long as Dearly Departed is in your graveyard, each Human creature you control enters the battlefield with an additional +1/+1 counter on it.
9/22/2011 The effect is cumulative. Human creatures you control will enter the battlefield with a +1/+1 counter for each Dearly Departed in your graveyard.
9/22/2011 In most cases, when determining whether a creature entering the battlefield under your control should get a +1/+1 counter, you'll simply look at what the creature will looklike on the battlefield. You'll consider any effects affecting a creature entering the battlefield under your control.