The Safari 3 public beta has been out for a while now, and will be included with Leopardwhen it comes out. If you haven't tried it out yet, you can download it for free from the Apple site. The following tips include things that will be useful to the average user as well as some more interesting tricks for more experienced users.

Merge Windows
Safari 3 now allows you to drag and drop tabs. You can drag a tab off the bar to create a new window or drag it onto an existing window to add it. You can also use this to rearrange the order of your tabs. If you have lots of open windows each with different numbers of tabs, there is an easier way to get them all into one instead of dragging and dropping. In the Window menu you will find the "Merge All Windows" command. This will instantly combine all your open windows into one tabbed window.

Enable Web Inspector
The Web Inspector allows you to easily see how the source code creates the web page. You can inspect various elements of the web page and view their style, metrics and properties. If you select an element in the inspector window, it will briefly be outlined in red on the web page.

To enable the Web Inspector, open up Terminal (located in Applications/Utilities), type the following line and press return:

defaults write com.apple.Safari WebKitDeveloperExtras -bool true

Now quit and re-open Safari. Open a web page and right-click (Control-click) anywhere. You should see a new "Inspect Element" item in the list.

Pie Chart Loader
Normally Safari indicates how far a page has loaded using the address bar as a progress bar. The box gradually fills with colour from left to right. If you want, you can easily change this to the pie chart type indicator that is used in Mail. Again, open up Terminal (in Applications/Utilities), type the following command and press return:

defaults write com.apple.Safari DebugUsePieProgressIndicator -bool true

To switch back to the old progress bar, simply repeat the above command with false instead of true.

Bookmark all tabs
This new feature obsoletes the tip I wrote last month about bookmarking all tabs in Safari 2. Doing this is now much simpler - you just need togo to the Bookmarks menu. Here you should find an item that says something like "Add bookmark for these 4 tabs...". The default settings creates a bookmark called "Saved Tabs" in the bookmarks bar. This is actually a folder of your tabs, but it has been set to automatically open all the pages in tabs when clicked.

Others
There are loads of other new features in Safari 3 that are well known or don't really require any explanation. For example, the find command now dims the page and highlights the words you searched for, web history now indexes the text content of the page for easier searching, you can reopen the last closed window or the windows from your last session and all text fields are resizable.