Yes. At the ArcGIS 8.1.2 release, the Selection tab was added as an additional table of contents display feature. This tab must be added manually when a new document is opened. The tabs you wish to display cannot be changed within the default settings of the application. If you wish to change the tabs that are displayed in your table of contents, you must do so with each particular map document. The default ArcMap behavior cannot be modified to modify the table of contents tabs.