Hi David Byrne,
By default the SiteTabStrip control is bound to CmsSiteMapData source and once you create a page a new tab is dynamically added to the TabStrip. There are three options here.
1. Use Siteffinity's backend and modify page names through Pages section.
2. Create a custom control that is bound to a different data source or add your tabs declaretively
3. Modify Sitefinity\UserControls\Navigation35\SiteTabstrip.ascx.cs Page_Load event where the RadTabStrip is filled.
the Telerik team