Currently all images include an extension that specifies the format of the image (such as .jpg, .png, .gif, .svg, etc.) Ideally the image name should not include this information, since it doesn't matter to those who *use* the image whether it's a JPEG or a PNG. For example, it would be much better to be able to say [[File:Map of Europe]] than to have to say [[File:Map of Europe.png]]. The author of the article shouldn't have to know (or care) what format the image is in.
Additionally, if a new version of the image is uploaded which is in a different format, it must be uploaded under a different image name. Then all the pages that use the image have to be changed, and the history of the old image is lost (T25255). This is a lot of unnecessary hassle.
Fixing this can also standardize lower-case image extensions, so that we don't have images named Bleck.PNG or Mleko.JPG (T34660).
The only major problem I see with fixing this is in the conversion process, when something has to be done about images whose names are the same except for the extension.