I ♥ Faces has a few great tips for the new business page timeline on Facebook.
The Timeline is Your Default Page -- If you have a welcome page or other landing page, you can not set it as the default page. Now the Timeline is the default.
Cover Image -- You can add a Timeline Cover Image now. The size is 851×315 pixels. You can edit this photo at anytime, so start designing it now.
Custom Apps Will Still Work -- You can customize the images for your apps, but only able to highlight a few. So choose wisely.
Click this graphic for more information!