"Describe" stage in UploadWizard has an option "Copy information to all uploads following..." and clicking it allows you to copy descriptions, categories and other metadata used in the first file to all the other uploads. When copying categories or descriptions the copied text should not erase existing text. In case of copying categories they should be added to already inserted categories. Similarly when copying description the copied text should not erase existing one, but should be merged, or maybe if the script detects that some descriptions are already filled it could give you an option of append / prepend or replace existing text. In my case I was uploading files from Flickr and the image description always shows up as title, which is fine but I need to copy them to description field. The easiest way to do it is to prepend {{subst:PAGENAME}} to description field, which at the moment has to be done by hand. In other cases all images in the flickr album are related to a specific place and descriptions only make sense in the context of that place so I need to add first sentence explaining the location.

I also think the name of the section should be just "Copy information to all uploads ...".