The following last names were recently set to "heritage" after being available for only 18 days. I have been checking frequently and they are surely retired now. They haven't appeared on any Join Now page since 2008-04-01.
Example:
http://slnamewatch.com/last_name_Morrow.html
Details for last name Morrow
Date Opened 2008-03-14 23:08:05
Date Closed 2008-04-01 13:33:46
Usage Count 83
http://slnamewatch.com/last_name_Bynum.html
Details for last name Bynum
Date Opened 2008-03-14 20:08:06
Date Closed 2008-04-01 13:33:46
Usage Count 13
http://slnamewatch.com/last_name_Dougherty.html
Details for last name Dougherty
Date Opened 2008-03-14 14:08:03
Date Closed 2008-04-01 13:33:46
Usage Count 33
http://slnamewatch.com/last_name_Spivey.html
Details for last name Spivey
Date Opened 2008-03-14 02:08:04
Date Closed 2008-04-01 13:33:46
Usage Count 20
http://slnamewatch.com/last_name_Steward.html
Details for last name Steward
Date Opened 2008-03-14 02:08:04
Date Closed 2008-04-01 13:33:46
Usage Count 51
...hundreds more examples at : http://slnamewatch.com/index.php?action=list_records&status_filter=heritage&sort_order=DESC&order_by=days_active&cur_page=16
(volatile link) (These counts can be confirmed using the in-world people search tool and the resulting avatar's join dates.)
This action wouldn't be much of a problem, just VERY lucky for the people who chose these names, and a little unfair to the rest of us, except in their place there are only 100 new last names to chose from. They are filling up very quickly! Since you did not release a comparable number of fresh last names to replace them, you should have kept some of those less-than-overused names active. I'm not sure how you can resolve this fairly. Please more careful in the future? thank you.