In a recent Rick Riordan blog, he was asked a question:

"Would you ever do something on Norse mythology?"

His answer:

"This is definitely the question du jour because of the Thor film. Believe me, I’ve had ideas for a Norse series for many years, long before the film came out. The problem is finding the time to write it. Maybe once I’ve finished the two series I’ve got going, I can turn to that, but right now my hands are full. Haven’t seen the Thor movie yet, as I’ve been on tour, but I plan to. I grew up on the Thor comics. Like the film, the comics take some pretty huge liberties with the Norse myths, but they’re still fun."

Likey or not? Honestly, i'm very optimistic that this is, if it will ever be made, going to be a huge success like PJO. I love all RR's books and I support him fully, unlike some "fans"