Same problem here, never happened prior to Karmic but now it's very common in Nautilus - any time I move a file that is represented by a thumbnail from one folder to another, Nautilus can't show the entire contents of the destination folder - sometimes Nautilus won't show anything, other times it shows everything but the file just moved. Any file that uses a thumbnail seems to be able to set this off - not just videos, but PDFs, and document files if an OpenOffice thumbnailer extension is installed. Closing and restarting Nautilus doesn't seem enough to reliably fix it.
Same problem here, never happened prior to Karmic but now it's very common in Nautilus - any time I move a file that is represented by a thumbnail from one folder to another, Nautilus can't show the entire contents of the destination folder - sometimes Nautilus won't show anything, other times it shows everything but the file just moved. Any file that uses a thumbnail seems to be able to set this off - not just videos, but PDFs, and document files if an OpenOffice thumbnailer extension is installed. Closing and restarting Nautilus doesn't seem enough to reliably fix it.