The free download is here: http://www.apple.com/safari/

Apple claims that it is the fastest Web browser on the market, but it is actually almost the fastest.

The fastest browser is still Google Chrome.  That's not just me saying it; I read a ZDNet report today, including actual performance statistics.  Safari 4.0 is very fast.  Chrome is just a little bit faster.

The final release of Safari 4.0 definitely shows improvement over the beta.

For one thing, I am so happy they decided to do away with the giant tab that stretched across the window titlebar.  That was remarkably ugly.  Instead, it now opens normal tabs just below the toolbar.  (Like IE8 and Firefox do.)

The Refresh button is still too small and almost hidden within the Address bar.  The browser menus are very similar to Google Chrome; they exist in two icon-only buttons all the way on the right side of the toolbar.

If you're a Safari user, I'd be interested to hear what you think of the new release.