I just noticed that the default landing tab on my Social Media SEO Facebook Fan Page was not adjusted for the new width policy that Facebook launched about a month or so ago.
Previously, I think the width of custom tabs on the Facebook Fan Page was around 570px.
But the new Facebook custom tab / FBML page width is 520px.
So if you have any custom tabs on your Fan Page, you might want to go back through and see if your images are looking right on your Facebook page.
Again, it’s 520px for the new Facebook Fan Page width.