I know, I know. Everyone who has any interest in this kind of thing is waiting anxiously for the new Ubuntu release. So I will shamelessly exploit that anticipation by mentioning that an updated distribution for Debian GNU/Linux "squeeze", 6.0.3, was announced over the weekend. Well, announced, but not quite entirely available yet. Most of the ISO images have been updated, but the Live images have not yet.
As is usual with this kind of Debian interim release, this is not a new version, it is only a rollup of the updates, patches and new packages that have come out since the last point update. If you already have Debian installed, you can get all of this by just pointing to a current Debian mirror and updating. The Release Announcement contains a complete list of security fixes and package updates. If you frequently install/reinstall Debian from scratch, it is probably worthwhile to download the new ISO images.