I have seen this too. I have a stable build from a few months ago and haven't updated for a while. Recently (few days ago, maybe Sunday) I did a backup and then update/upgraded. My package list was long and was over 480MB.
I allowed it to complete and I got exactly what you're describing. Regenerated Orbiter (100%) then just sits there.
I have returned to my backup now, but I can confirm the same problem from my recent update attempt..