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Why does this work? (Binding in a Panorama-Template, Windows Phone 7)
<controls:Panorama x:Name="PanoramaMama" Title="my header">
    <controls:Panorama.TitleTemplate>
        <DataTemplate>
            <TextBlock Foreground="Red" Text="{Binding}"/>
        </DataTemplate>
    </controls:Panorama.TitleTemplate>
    <controls:Panorama.HeaderTemplate>
        <DataTemplate>
            <TextBlock Foreground="Blue" Text="{Binding}" />
        </DataTemplate>
    </controls:Panorama.HeaderTemplate>

    <!--Panorama item one-->
    <controls:PanoramaItem Header="item one">

        <Grid/>
    </controls:PanoramaItem>

    <!--Panorama item two-->
    <controls:PanoramaItem Header="item two">
        <Grid/>
    </controls:PanoramaItem>
</controls:Panorama>