With the recent new role out of Facebook’s new Timeline for pages, I thought I would just jot down the image sizes that you can now make use of so keep them handy. I am sure like me, you will think of better ways to use the images as times goes on.
Main Image: 851 x 315 pixels
Mini profile image: 180 x180 scaled to 32 x 32 pixels This is the small one directly under the main image.
Apps Image: 111 x 74 pixels
Milestone image: 843 x 403
Old welcome page app space was 520 wide, but can now be 810 pixels wide, so lots like your website.