TUAW reports that Apple has released a new security update for OS X
Yes, as you can see above (and in a Software Update near you), Apple has released Security Update 2010-006, the latest OS X issue-fixer of the year. It's recommended for all users, so run your SU, let it download and install, and you'll be good to go.Apple releases Security Update 2010-006
This one apparently fixes an issue where a remote attacker could have snuck into AFP shared folders without having a password. Apple releases OS Security Updates a few times a year, and given how simple it is to update and install them, you should go ahead and update as soon as possible.