In private correspondance, a high-ranking editor for the OED told me that they haven't drafted an entry for "bling-bling." They haven't posted it online. They entry, he says, "isn't there." They are looking at "bling bling" like they look at all words: too see if it's acceptable. They receive citation slips (well, the modern version) for any word, and then what makes the cut is decided later. Big yawner non-story.