Facebook is going to change the tab width of all Facebook fan pages and applications from August23, 2010. The current maximum limit for tabs on fan pages and application pages is 760 px which will be reduced to 520 px, according to a blog post on the Facebook developers blog.

Facebook will roll out an app so that designers and page administrators can preview the transition from the older format to the newer one. This is to ensure that page administrators can test the newer settings before hand and make necessary changes to the source codes of their applications.

If you are a Facebook application developer, it’s high time you change the design of your apps because from August 23, the newer model will be implemented whether or not your application adheres to the latest design principles.

In the coming weeks Facebook will notify all page administrators via messaging in profile boxes. In the Help Center, the “Boxes” tab, boxes on profiles and Pages, and application info sections will be going away.

According to Facebook, the newer design is being implemented to simplify the navigational aspects of Facebook applications and fan pages. It will also reduce design complexity for developers. The developer roadmap will be thoroughly updates in the coming weeks.

So those who are on their way to coding a Facebook app or something, pack the bags till August 23rd. You don’t want your application to break in the middle, do you?

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