I'm stumped. I'm working with the 3.5 runtime in VS 2008. I've added "using
System.Collections.ObjectModel". ObservableCollection is not known. In fact,
if I type "System.Collection.ObjectModel." the intellisense only lists
Collection<>, ReadOnlyCollection<> and KeyedCollection<>. In the object
browser, I find ObservableCollection under "WindowsBase", and it's listed as
ObservableCollection. How can I make use of this class so I can bind a WPF
element to my custom Object?