Various bugs have been popped up about the upload summaries [1,2] provided when an image is uploaded from Special:Uploads or as a lead image for an article.
It seems in the case of Special:Uploads the edit of summary could be more useful and actually provide some detail describing what the image is or where it might be useful.
In the case of uploading from a page in conjunction with the above it would also be nice to know which page the user uploaded from e.g. "Uploaded lead image for X article"
 bug 50265
 bug 51474