What you can also do is put some code such as follows into a file named "signup-xtra.php" in your main ListMail folder.
This example removes users from lists 2 and 3 when they subscribe or are added or imported to List 1.
<?phpif($list=='1'){ mysql_query("update $utable set cnf = '2' where (list = '2' or list = '3') and email like '$email';");}?>
I will consider the best way to make this an option and put it on the list of future updates. I think a simple text box on the List Settings page accepting comma-delimited list numbers would work. "When a user is added, remove them from these lists [2,3 ]"
Regards