We have an open case and have it escalated as well. Still waiting for a response back as to what is going on. We are not a big shop, and rarely have more than a couple hundred synch activities pending at any given time, but I have at least 3x4 times a day where my queue is backed up by more than an hour. In a world that we live in, where speed is crucial to converting leads, this kind of delay is significant and business impacting.
I would also encourage you to escalate.