truheart on "Change item order for +Add menu in the admin bar"

I hope the title makes sense. Basically I would like to know how to change the order of the items a user sees when he clicks on the "Add" button in the admin bar. For instance, say you have a couple of different post-types where a user can add a new post directly from the admin bar. How do you get it to display the post-types in the order you would like? The default post-type and media items are always on top and it would be great to be able to have control over this. Thanks guys.