Bill,

Unfortunately the binding options for the fills of the datapoints are constrained at the moment, so this will require some code behind. I've put together a sample of how you might achieve some of this behavior.

Markup:

<UserControl x:Class="SilverlightApplication23.MainPage"

    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"

    mc:Ignorable="d" d:DesignWidth="640" d:DesignHeight="480"

    xmlns:igChart="clr-namespace:Infragistics.Silverlight.Chart;assembly=Infragistics.Silverlight.DataVisualization.Chart.v9.2">

  <Grid x:Name="LayoutRoot">

        <igChart:XamWebChart x:Name="theChart">

            <igChart:XamWebChart.Series>

                <igChart:Series ChartType="Pie"

                                DataSource="{Binding}"

                                DataMapping="Label=Label; Value=Value" />

            </igChart:XamWebChart.Series>

        </igChart:XamWebChart>

  </Grid>

</UserControl>

Code Behind:

public partial class MainPage : UserControl

    {

        public MainPage()

        {

            InitializeComponent();

            DataContext = DataItemsViewModel.GetTestData();

            theChart.Series[0].DataPoints.CollectionChanged += new System.Collections.Specialized.NotifyCollectionChangedEventHandler(DataPoints_CollectionChanged);

        }

        void DataPoints_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)

        {

            for (int i = 0; i < theChart.Series[0].DataPoints.Count; i++)

            {

                theChart.Series[0].DataPoints[i].Fill =

                    (DataContext as DataItemsViewModel)[i].Fill;

            }

        }

    }

    public class DataItemsViewModel : ObservableCollection<DataItemViewModel>

    {

        public static DataItemsViewModel GetTestData()

        {

            DataItemsViewModel ret = new DataItemsViewModel();

            ret.Add(new DataItemViewModel() { Label = "test1", Value = 4 });

            ret.Add(new DataItemViewModel() { Label = "test2", Value = 8 });

            ret.Add(new DataItemViewModel() { Label = "test3", Value = 2 });

            ret.Add(new DataItemViewModel() { Label = "test4", Value = 1 });

            return ret;

        }

    }

    public class DataItemViewModel

    {

        private static int _currentColorIndex = 0;

        private static object _colorIndexLock = new Object();

        private int _colorIndex = 0;

        private Color[] _colors = { Colors.Black, Colors.Blue, Colors.Brown, Colors.Cyan, Colors.DarkGray,

                                     Colors.Gray, Colors.Green, Colors.LightGray, Colors.Magenta, Colors.Orange,

                                     Colors.Purple, Colors.Red, Colors.White, Colors.Yellow};

        public DataItemViewModel()

        {

            lock (_colorIndexLock)

            {

                _colorIndex = _currentColorIndex % (_colors.Length - 1);

                _currentColorIndex++;

            }

        }

        public SolidColorBrush Fill

        {

            get

            {

                return new SolidColorBrush(_colors[_colorIndex]);

            }

        }

        public string Label { get; set; }

        public double Value { get; set; }

    }

-Graham