This is per CiviCRM forum post http://forum.civicrm.org/index.php/topic,3608.0.html
Basically, the patch files attached allow you to select whether or not to print one mailing label per unique address. It also creates a list of all people at that address and prints them one name per line as below:
1234 Street Rd
The consolidation of names to one address saves multiple mailouts to the same address.
I created an updates directory in /sites/all/modules/civicrm/ and dropped these patch files in there. Then I changed directories into this directory and patched using the following commands:
patch ../CRM/Utils/Address.php Address.diff
patch ../CRM/Contact/Form/Task/Label.php Label_php.diff
patch ../templates/CRM/Contact/Form/Task/Label.tpl Label.tpl.diff