I'm not sure "Hearttaker" can actually be finished. I remember getting a proper quest reward when I turned in my first goblin heart, but after that I just got a small chunk of XP and gold for each new heart. So I assumed that the quest was basically 'complete' after the first turn-in, but it stayed in your log in case you found other hearts.
It's possible that I missed some Goblins, and if I'd found them the quest might have been officially 'complete', but I wouldn't worry - the XP and gold from extra hearts wasn't much anyway.
