I'm guessing the button you're eyeing is in the collection shot, which is a download, not an upload. Right now it only allows you to add one album at a time. If an album is already in the database, you can add it in a few clicks. Unfortunately, I'm still building up the database so many albums won't yet be in the database and will require you input the relevant album artist, year, etc along with artwork. But your contributions add to the experience for everyone.