Looks I'm a few years late here but didn't see a reply how to do it in this thread.
I think one way to see the emails that are pending if you were to create a smart list that was configured to show "Was Sent Email" And "Not was Delivered Email" where email "is" the one you are looked at.
That‘s a start, but doesn‘t really address only what is queued. You would have to exclude bounces and people exceeding comm limits.