IValueConverter moved from System.ComponentModel to System.Windows.Data PropertyGroupDescription moved from System.ComponentModel to System.Windows.Data Its new constructors allow you to write: Dim g As System.ComponentModel.PropertyGroupDescription g = New System.ComponentModel.PropertyGroupDescription() g.PropertyName = "Status" g.ValueConverter = conv like this: Dim g As System.Windows.Data.PropertyGroupDescription g = New System.Windows.Data.PropertyGroupDescription("Status", conv) ICollectionView properties were renamed Sort --> SortDescriptions GroupBy --> GroupDescriptions and much more ... Unfortunatelly MS released December CTP before I could complete this. So stay tuned to receive information about December CTP! ATM I'm downloading and Installing Vista December CTP WinFX December CTP WinFX December CTP SDK Microsoft Visual Studio Code Name "Orcas" Community Technology Preview - WinFX Development Tools