While on vacation a number of you let me know i have two out of offices being sent - one accurate - one over a Year old! Turns out the one that is a year old was created in a custom internal tool and wasn't visible to the Outlook 2007 Out of Office Assistant.
To fix this i needed to use a switch called "Cleanrules" on Outlook.exe.
-Note do NOT run this until you have backed up your existing rules!
For more information about this switch see:
Rules That You Created in Outlook 2002 Are Not Visible in Outlook 2003, but the Rules Are Visible in OWA