As a seasoned component developer I was a bit disappointed when I first made the move to .NET with respect to (really only) one thing:  the ability to scope the property getters and setters individually.  Back in the good ol' VB 6.0 and C++ days, it was common practice to create a property that was readonly externally and public internally to the application.  This simplified semantics and the programming model was simpler.  However, when I came into .NET I found abruptly that I would have to create a readonly property and then a separate accessor function to set the value of the property internally:

public int Age {
   get { return _age; }
}

internal void setAge(int value) {
   _age = value;
}

I am very excited to learn that in the Whidbey (Visual Studio 5.0) timeframe we'll get scoped property accessors.  Now the syntax would be like the following:

public int Age {
   get { return _age; }
   internal set { _age = value; }
}

As Eric Porter reminds us, this is not just a C# feature, but you'll be able to do the same thing in VB.NET:

Public Property Age() As Integer
   Get
      Return _age
   End Get
   Friend Set(ByVal Value As Integer)
      _age = Value
   End Set
End Property

I can't wait for this enhancement!