Can I see a live viewer count during a broadcast?

Generally, no unless you are doing a lengthy broadcast.

DaCast provides users with a deep analytic back office that allows you to see how many people are watching a stream and other statistics related to it. The data is populated two hours after the initial point of broadcast, which makes it a good way to see the success of a particular stream as early as possible but not to get an idea of how many are watching while you are in the midst of streaming.