Kirk,
Just to let you know, I too get ghosting sometimes. But I haven't found a way to reproduce it consistently. I think switching to another application has got to do something with it, but I'm not sure...
The cure is relatively simple: find the contact sheet that causes the ghosting (it can be another one from the one showing) and close it; the ghost panes are gone!
I'll let you know if I found a way to consistently reproduce this problem.
Cheers,
Hayo