The rectangular cover images are a great choice for your blog posts, discussion boards, Twitter, and pretty much anything else... except for Facebook.

For Facebook you should select one of the Square options (a square on a white background, or a square on black). Facebook does cruel and unusual things to the rectangular images, but the square cover images have been raised in hardened circumstances and trained to withstand torture. So they'll be all right.

Internet Explorer users and some Mobile Device users may have problems when trying to save images. Find out how to fix that in the Pulp-O-Mizer User's Guide.