Johns also made mention of a few seemingly random characters shortly after the first quote about New Guardians.
You ever notice how a lot of villain in Green Lantern have mustaches?! Sinestro, Hector Hammond and Krona the Rogue Guardian! Bizarre! - Geoff JohnsCompletely random or does Krona pop up again and Johns is merely commenting on something he's been researching and noticed? Could Krona play a part in Blackest Night? Maybe return as a new Guardian? Krona played a major role in Nekron's first appearance and helped him return to our universe. He's also a major power threat and former Guardian of the Universe. Curious and curiouser.