If you are an administrator on any Facebook fan page, chances are you’ve seen the message on the top of your fan pages that Facebook is changing the way they are doing tabs on pages, most notably the size of the content that lives on tabs.
Basically, they are narrowing the width of these tabs from 760 pixels down to 520 pixels. If you have created custom FBML tabs, you’ll need to login in as soon as possible and either resize or redesign your tab content to make sure it fits correctly in the new sizes.
Here’s a visualization of the difference:
This is quite a reduction in size – especially if you’ve created custom layouts or other images for those tabs. Facebook is explaining the change this way:
These updates are designed to simplify navigation for users, reduce complexity for developers, and enable us to build the next generation of tools for growing your business with Facebook.
Said another way: we need the room for ads. That’s my take.
The other change: the “Boxes” tab, boxes on profiles and Pages, and application info sections will be going away. I don’t know if many schools were using these features on their fan pages, but be aware those are going away as well.