What format are the photo files in?
OK...very strange. I had the 'Destinations' tab collapsed. When I clicked to expand it the photos suddenly showed up!
I was attempting to 'Add' photos before (in which case the Destinations is irrelevant) In ''Copy'' or 'Move' the destinations seems to want to be expanded as a tab. Now when I go back into 'Add' the picture imports are working. Thanks for your help and I hope that this might help someone else.
I'm glad I found your problem because I had exactly the same thing happen. All of a sudden, LR import doesn't show any photos on my HD available for import. After a couple of hours searching the forum I ran into your post. I performed the same Destination magic you described and "voila" everything is working again.
NOTE TO ADOBE: What happened here??
Awasome! I had the same problem! Thanks