Apple released a developer preview of the upcoming version of its web browser Safari to registered Developers. The Safari 4 Developer Preview is available for Mac OS X Tiger/Leopard and Windows. While the main changes are not visible to the user the most significant visible new feature is the overhauled Web Inspector.
Read more - Safari 4 Developer Preview - Better Performance, Overhauled Web Inspector, New CSS [Update] › Blog › kremalicious.com Matthias Kretschmann | Photography & Design

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Another site: Apple Gives Developers Safari 4 Preview | World of Apple