Property/Method descriptions

Does anyone know how to create the tooltip-like descriptions that pop up in the Intellisense window for a custom property?
I thought this example from MSDN would do the trick, but so far I haven't had much luck. Not surprisingly, the documentation in MSDN doesn't give a great example. If I call this object, the GetType method gives me a description to the right of the Intellisense window, but the MyImage property does not.

Imports System.ComponentModel
Public Class MyObJect
Dim image1 As Image

<Description("The image associated with the control"), _
Category("Appearance")> _
Public Property MyImage() As Image
Get
' Insert code here.
Return image1
End Get
Set(ByVal Value As Image)
' Insert code here.
End Set
End Property
End Class

As far as I know, the Description and Category as you have them only appy to properties when in Design mode. I tried add Intellisense tooltip-like descriptions for properties and methods, but was unsuccessful. So, I'd also like a little help on this topic.