What do we know about Eragon book 4?

• The cover of the fourth book will feature an emerald (green) dragon
• Murtagh and Thorn will play larger roles than in the previous books.
• With the first parts of Eragon’s prophecies having been resolved in Eragon and Brisingr (weapon under the Menoa Tree, “There is a doom upon you, but of what sort I know not. Part of it lies in a death …”), we can expect the remaining prophecies to come into play:
  • Eragon’s vision of him and another leaving Alagaesia forever with their dragons
  • The Rock of Kuthian and the Vault of Souls
  • An “epic romance” (“I cannot say if this passion will end happily, but your love is of noble birth and heritage. She is powerful, wise, and beautiful beyond compare.” – Angela, Eragon… it is arguable that this romance/passion has already existed for Arya with a bad ending)
• The origin of werecats will be thoroughly explored

from Shurtugal.com

What I really want to know is, “When will the book be released!?”