When one split pane is closed the other should maintain its position
Should have a popup menu on the desktop
Need to complete windows menu (MenuModel needed?)
Need to carefully check event delivery
Changing Look & Feel when tabs not visible causes the tabs to have old look and feel
Toolbar: No externally accessible toolbar menu
Toolbar: Docking/Undocking toobars doesnt work properly

ManagedPage has too many methods, inconsistent with PageEvent
Component too closely identified with currentTab, 
   it is difficult to find current Page
   it is difficult for page to close itself

No way to get the initial open and select events from PageContext.