The 10.4.8 Update is recommended for all users and includes general operating system fixes, as well as specific fixes for the following applications and technologies:

- connecting to wireless networks using the EAP-FAST protocol
- Apple USB modem reliability
- using OpenType fonts in Microsoft Word
- compatibility with 3rd party USB hubs
- scanner performance
- RAW camera support
- printing documents with Asian language names
- performance of the Translation widget
- broadband network performance
- security updates

Check Software Update to grab the download.  It’s a whopping 211Mb for Intel users.