I would also like the option to have this plugin work by liking a FB page, and not a URL. As vdsn mentioned, a “Like” on my facebook page is more valuable to me than a like on a URL, because URLs may change, but the facebook page is where I want the likes to show up.
If a user has already liked my FB page, then I’m fine with them having access to all FB-locked downloads. My plan is to offer one main download for FB likes, and everything else through tweets anyways.