Oh dear. I seem to be in the minority who actually quite like it ... it conveys a suitably doom-laden theme (after the ending of HBP it wasn't really going to be "HP and the Fluffy Slippers"), and probably simply refers to the Horcruxes or their locations? (And again, as I've said elsewhere, she may have gone for a phrase that wasn't used elsewhere, hence the slightly odd sound. "Deathly Hallows" was a no-result on Google yesterday when I tried it. Juts tried again in fact and it still is, although I bet that doesn't last long!)