Check Software Update on your Mac, Apple has released the latest Safari update.

Here is what Apple has to say about Safari 4.0.4:

This update is recommended for all Safari users and includes improvements to performance, stability, and security including:

- Improved JavaScript performance
- Improved Full History Search performance for users with a large number of history items
- Stability improvements for 3rd-party plug-ins, the search field and Yahoo! Mail

For detailed information on the security content of this update, please visit this site: About Apple Security Updates.

You can download the update here.