How can I filter meeting requests and other calendar items in Outlook 2011 with a local client-side rule?
If I understand your question correctly, you can use the Rules Wizard to create a rule which identifies any item "which is a meeting invitation or update". (This option is near the very bottom of the list; you might have to scroll down.)
For Mac Outlook 2011 I use the following client side rule for meeting requests:
Specific Header > Content-Class > Contains > calendarmessage
Better late than never :)