Great plugin, here are some tips and ideas for the developer and anyone who adds this plugin to their site.
1. Change the default PNG - the documentation is probably being updated as I write this, but the default image is in your site /wp-content/plugins/open-graph-protocol-tools/default.png and probably doesn't match your branding. Switch that image out for something that does and/or dynamically update the og:image meta tag with an image from your post.
2. Editing the style of the iframe (size and where it's placed) requires editing the plugin. It's a 2 min fix to change the plugin code, but then you have to re-do it every time, so it would be great if the plugin removed the element CSS and instead recommended adding a new class to the theme's stylesheet, plus some recommended styling. It would also be cool if I could set the size of the iFrame to match my site.
Anways, thanks a ton Mr. Joe Crawford for knocking this out so fast. Very impressive.