Breaking News!
Facebook has just recently added the ability to Unmerge your Fan Page from your Place Page.
Many Page Admins have been upset with Facebook because they were prompted to merge their Fan Page and their Place Page but when they did, the new merged Page lost Top Level Tabs, ability to set your Default Landing tab, and it narrowed the width of the fan page to 490 from 520 pixels.
NOW YOU CAN UNMERGE! This is great news for fan page Admins.
Please see the image below for the locations of the unmerge link.
You will be prompted with this:
Full Facebook information on Merge issues on Facebook is here.