So far, I am thrilled with the decision to integrate online quizzes into my courses this semester (see my previous post). Over 90% of the students enrolled in my courses come to class having competed the readings for that day, enabling them to engage in discussion on a variety of topics.
You can set up quizzes with time limits, banks of questions to deter cheating ("pools" in Blackboard), due dates, and in random order.
You can set up quizzes with multiple choice and true/false questions (among other options).
Students can take quizzes at any time up to the due date of the quiz, allowing night owls or early risers to complete these assignments at the optimum time for them.
Grades go directly into Blackboard, so you don't have to take time in class to administer quizzes or grade these after class.
It encourages students to budget their time and operate on a regular schedule.