Asp.net - Listbox Bound To ObservableCollection (in .NET And Silverlight)?

I'm trying to bind a listbox to an ObservableCollection and keep the listbox updated when items are added to the collection. I have a class called CollectionOfBlogs:

Public Class CollectionOfBlogs
Implements INotifyPropertyChanged
Public Event PropertyChanged As PropertyChangedEventHandler _
Implements INotifyPropertyChanged.PropertyChanged

[code]....

Beyond this, I have a simple textbox and button on a page. When a name is entered into the textbox, and the button is clicked, I call the addBlog(passing in name from textbox) sub routine in the ITRSBlogs Class (back up the page a bit) to add the item to the collection.Problem is, when I add an item to the collection, the listbox is not updated.