There are several updates to Discussions and Quizzes.
Discussions
Faculty can now add a Due Date to a D2L Discussion in the Discussion Editor. The Due Date is for first post/thread and does not track subsequent posts or threads.

When reviewing post submissions for evaluation, we will see a “Posted” column that let’s us know when a Student posted or how long after the Due Date a Student posted.
Quizzes
Quiz questions can now be set to 0. This can be useful for creating Questions on Academic Integrity and Honesty within a quiz.

Additional tutorials can be found on the D2L Self-Paced Tutorials for Faculty and Staff Wiki page.