Documentation say's
"A panel must be a sibling to the header, content and footer elements inside a jQuery Mobile page. You can add the panel markup either before or after these elements, but not in between.** A panel cannot be placed outside a page, but this constraint will be removed in a future version**."

If in future if Panel is placed outside page, will it be something like a fixed Panel / Panel floating above Pages and Panel stays on change page?

Example: Using panel to show a left navigation using tree structured menu.Selecting an item changes the page but panel stays as it is on page change.

Will be usefull for tablets...