In reply to:

Do the users get any kind of a message back when the logos aren't approved?

Not yet. My admin page has "Approve" or "Delete".

But the messaging is something I want to implement soon, but I have held back on too many new features until I get it all moved into an actual database. Hopefully this weekend will see it there. Because if I don't get it into a database soon, all the new features are going to make that job much harder.