New version of Safari has been released as noted below
Safari 6 – New browser version emerges
http://www.apple.com/safari/
http://support.apple.com/kb/HT5364
QUOTE: The new advanced features in Safari make it an even better place to explore the web. Safari searches even smarter so you’ll find web pages faster. It shows you all your open tabs in a great new way. Right from Safari, you can tweet web pages, post them to Facebook, or share them via Mail or Messages