In Response to the question by Kristina on dealing with users that have organized reoccuring meetings.
When the user is removed it will end up ophaning the original meeting. So it is best to remove all reoccuring meetings from the organizers calendar and send updates that they have been removed prior to deleting the mailbox.
Also it was brought to my attention that I should mention something about users leaving the company under less than amiacable terms.
If that is ever the case please make sure that you purge all rules for that user after they leave the company. Otherwise they could have setup a rule to forward all of their email to an external address.
-Matthew Byrd