Assuming you don’t have any link shares in place (Digg, OpenID, MySpace etc), the process should be quite simple:
http://www.facebook.com/help/contact.php?show_form=delete_account (you have to be logged in to use the link) and then don’t access the account for 21 days. Some say 14 days, but what’s the hurry? Some recommend no interaction with Facebook at all (pages, groups, public content) – this is related to cookie updates and FBCDN backtracks.
Once completed, that should move from “deactivated” to “deleted” status.
Is anything going to be really removed? Facebook alone know(s)…