In Visual Studio 2010, you can add the following lines to the "[Visualizer]" section of your autoexp.dat to get reasonable previews of vector types. This is highly recommended, otherwise the watch window becomes a little cluttered.
cml::vector<*> {
     preview(
        #switch ($e.dimension)
        #case 2 ( #("[", $e.m_data[0], ", ", $e.m_data[1], "]") )
        #case 3 ( #("[", $e.m_data[0], ", ", $e.m_data[1], ", ", $e.m_data[2], "]") )
        #case 4 ( #("[", $e.m_data[0], ", ", $e.m_data[1], ", ", $e.m_data[2], ", ", $e.m_data[3], "]") )
        #default ( "..." )
     )
     children(
        #array(expr: $e.m_data[$i], size: $e.dimension)
     )
 }
 cml::fixed_1D<*> {
     preview(
        #switch ($e.array_size)
        #case 2 ( #("[", $e.m_data[0], ", ", $e.m_data[1], "]") )
        #case 3 ( #("[", $e.m_data[0], ", ", $e.m_data[1], ", ", $e.m_data[2], "]") )
        #case 4 ( #("[", $e.m_data[0], ", ", $e.m_data[1], ", ", $e.m_data[2], ", ", $e.m_data[3], "]") )
        #default ( "..." )
     )
     children(
        #array(expr: $e.m_data[$i], size: $e.array_size)
     )
 }