Maybe we could have one of the bots leave a thank you message when one of the images is used (you could make that a bit higher if that becomes to spammy). A user should only get the message once and should have a link to a tool to show the usage of images uploaded by a certain user. Do we already have such a tool? I think this would be a great motivator,
not only for Wiki Loves Monuments but for Commons as a whole.
Maarten
I agree, with the correction that bot should not react if the user themselves added the picture. I have never heard of this functionality, and also never seen anything like lists he most used files (is this the Wikipedia logo? I know that one of my files is used 20 times, but I am sure files in templates, for instance, can be used in hundreds of articles).
Cheers Yaroslav