Safari 4 beta

Apple released Safari 4 beta for Mac and Windows, it can be downloaded from Safari’s page.
Here’s a list of Safari 4’s features:

• Cover Flow — You can browse through your site history or bookmarks the same way you browse album covers in iTunes
  Top Sites — look at renderings of your favorite sites, and open any one of them with a single click
• Full History Search — A clever way to visit sites you have been to in the past. You can type a word or phrase into the history search field and you’ll get a cover flow view of sites that match your criteria
• Nitro Engine — Apple claims JavaScript now executes 30 times faster than IE7 and 3 times faster than Firefox
  Tabs on Top — Allows Safari to have multiple pages open at the same time in a single browser window, and to switch back and forth with a click. The new Safari beta gives you more room at the top of the sceen when in tabbed mode.
• Windows Native Look and Feel — The Windows Safari 4 beta more closely matches the look of other Windows applications and gives access to standard Windows fonts; Apple claims the same performance boost on Windows as in the Mac version

Apple press release: Apple Announces Safari 4 – The World’s Fastest & Most Innovative Browser.