Safari 5.0.3 is available direct from Apple for Mac OS X 10.5.8 or later and Windows XP, Vista and Windows 7. Tiger users must be running Mac oS X 10.4.11 for Safari 4.1.2.
For both Mac and Windows users, the update fixes an issue that could prevent users from submitting web forms. It also establishes an encrypted, authenticated connection to the Safari Extensions Gallery.
The latest version of Safari 5 for Mac also fixes an issue that could cause Web content to display incorrectly when viewing a Google Image result with Flash 10.1 installed.
Other fixes, according to Apple, include:
More accurate Top Hit results in the Address Field
More accurate results in Top Sites
More reliable pop-up blocking
Improved stability when typing into search and text input fields on www.netflix.com and www.facebook.com
Improved stability when using VoiceOver with Safari
Safari 5 was released in June, bringing sandboxed extensions, as well as expanded HTML5 support. It also added the ability to make Microsoft Bing the default search engine.