Rick Riordan has this to say, before he shut down from social networks to avoid spoilers:

“All seven demigods will have a resolution to their story, one way or another. You will know where all of the characters are and what’s happening to them. It really is all about wrapping things up and coming full circle to the story we started in The Lost Hero.” x

And regarding those people that are spreading spoilers, who somehow got their hands of a copy:

“I am aware of people posting spoilers,” he wrote on September 27, “Whether info is true or not, the posters have a special punishment waiting for them in Tartarus.”

As they say, the end is only the beginning. He's now working on his next series, not going too far from his previous works, the series is inspired from the Norse mythology. Who's excited for Loki? I know I am! The title of the first novel in the series was announced: Magnus Chase and the Gods of Asgard, scheduled for an October 2015 release. We should really make October Rick Riordan Month!

CHASE. Familiar, right? Annabeth Chase. So I'm thinking this could be someone related to her, a cousin, a long lost brother, or Magnus BANE! Hahaha… He kind of owned this name.

I'm sad that this series is ending. This series, as well as the Percy Jackson series, has made my life in some way amazing. You bet I'll be reading these series to my daughter.