In the past, I've rated Safari as the weakest of the various web browsers. The main problems I found was an inability to understand tabbed browsing, a poor design for the bookmarks, and a complete lack of customization, up to an including the inability to use any other inline search engines than Google and Yahoo.
A new version of Safari does nothing to fix any of the conceptual flaws in the design of the browser.
First, the good news. Safari is fast. It and the new Internet Explorer 8 are by far the fastest of the browsers. Some tests say that Safari is the fastest, but I doubt any human being could see any difference between it and MSIE8. But, still, fast is good and the improvement over older browsers is considerable.
They've also set things so it uses standard rendering of text, so web pages look right. You can use Apple's scheme if you want, but it's nice that Apple gives you the option to do things the way you want for a change.
In addition, Safari has the same private browsing feature that Google Chrome and MSIE8 have.
That's about it. Safari still doesn't understand tabbed browsing. They've improved things somewhat by adding a button to add a tab -- something that's essential since browsers don't create new tabs for inline searches.* But it's much harder to move tabs around once they're created. In all other browsers, you click anywhere on the tab and can move it. In Safari, you have to click on a tiny corner with a symbol whose meaning is completely opaque to the user. Why make it difficult?
Safari still has the same horizontal design for bookmarks that I just don't care for. It's better than in previous versions and I suppose the design allows for a cleaner look (Apple always chooses looks over functionality). But the lack of space means that you need to put your bookmarks into folders instead of just having them available.
I get the distinct impression that Safari's developers never bother with bookmarks and merely type in all the web pages they go to (It's quite clear they never use tabs).
As for customizations -- forget it. You can't even add additional search engines to the inline search. I search Wikipedia a lot, but Safari doesn't offer even that obvious option. The best browsers will let you search any site through inline search; Safari gives you two.
There are no add-ins. If you want a feature that's not in Safari, you're out of luck; there's no way to add it. No skins, either (though that's not really a flaw -- it's rare to find a skin that's worth using).
And there's no sign of innovation. MSIE now has the web slices feature. Google Chrome invented private browsing and uses the history to create favorites. Opera invented tabbed browsing, the speed dial, and Paste and Go. Firefox developed plug-ins. All come up with new and interesting ways to make browsing better.
Safari does nothing new. It doesn't even do many old things (like automatically creating a tab instead of opening a new browser).
But it's fast. If that's all that's important to you, use it (but check out MSIE8). But if you want a flexible web browser that does what you want it to do, use something else.
*Something I can't understand. Google Toolbar has done this for ages, yet if you type in anything in the search field in all browsers, your current page changes to the search engine. Not very useful if you're trying to look things up on the fly.