The new calendar in Blackboard is everything you've wanted it to be for years! One of the most important features of the new calendar is that it links directly to due dates for test and assignments. Once a due date is set, you can change it by just dragging it in the calendar.
If you haven't been using due dates, now is the time to start using them!
Watch the video at http://www.youtube.com/watch?v=pTdGOMAZhQY&feature=share&list=PLontYaReEU1uivbr7MFnCcdSgLgELAkRP to see how the new calendar works.
You can find complete documentation for the new calendar at https://help.blackboard.com/en-us/Learn/9.1_SP_10_and_SP_11/Instructor/050_Course_Tools/Calendar.