Update: This software update — as promised by Apple — locates and removes variants of the MacDefender program if present. Also, File Quarantine will now check with Apple daily to download new security definitions, so the company should be able to respond to threats much quicker. Apple has published information about this on its Support site.

Today, Apple has released Security Update 2011-003 for Snow Leopard. It can be downloaded via Software Update, or from Apple’s site.

It’s hard to say what Apple’s included in this update, as these are the notes:

Previous security updates have been incorporated into this security update.

If we hear anything more, we’ll let you know.