Apple updated Safari with the release of version 5.0.2 which is mainly bug fixes for improved compatibility and security:
* Fixes an issue that could prevent users from submitting web forms
* Fixes an issue that could cause web content to display incorrectly when viewing a Google Image result with Flash 10.1 installed
* Establishes an encrypted, authenticated connection to the Safari Extensions Gallery
Get it from Software Update as usual if you’ve yet being prompted.