I hope this is the right place for this ? I've gone from PSE1 to 3 and the thumbnails from PSE3 are black if saved in psd in My Pictures. If saved in tiff the thumbs are there. Is this a plot to make me use the organizer or am I missing something? Any help would be welcome.

Yes, it's a plot :)

PSD files no longer show thumbnails in the OS. I'm surprised you're getting black squares, I just get the Adobe logo.