Originally Posted by Lurking Grue
What's the status of the English translation regarding written works that are not main quest related?

The latest patch doesn't address the minor, non-quest related text translation and, from what I understand from the official forum, these texts are a low priority and may never be 100% done. If I were you, I wouldn't wait; they don't really detract too much from the game since they give no vital info anyway.