so, just an update...
i plugged my current time machine backup disk into the AEBS, and time machine wouldn't update to it. 🙁 said something about not having enough space on the drive to complete the backup. bummer. this threw me off because i had been using the drive for the last year with time machine, and never had this problem before. my macbook pro has a 250gb HDD, and this external drive is only 250gb. its a little small, but it should hold everything i need it to.
so, i reformatted the drive, plugged it back into the AEBS, opened time machine preferences, selected the drive, and it started the backup process. awesome! it took quite a while for the first backup to complete, but it completed.
i think i want to still find a larger external so i can partition it to also be able to store movies on it. then i can get CCC and use this current drive as a clone boot drive backup.