Based on the demos we've seen, we're reasonably sure none of the 10 top-secret things Apple CEO Steve Jobs said would be in the final release of Mac OS X 10.5 (a.k.a. Leopard) are in the build distributed to developers this August. That doesn't mean there still aren't interesting features in the demo version of Leopard left to discover. Most of the changes are to frameworks and other close-to-the-metal areas, of import mainly to developers, but some of the other changes we've seen will affect end users as well.
The most outstanding feature within Leopard at this stage is Finder, which looks exactly as it does in Tiger. Still, there are some changes that longtime Mac users will appreciate. First, you can (finally) change the grid spacing in Leopard, restoring a long-lost piece of functionality last seen in Mac OS 9. Second, if you select a filename and hit Enter to rename it, the Finder highlights only the filename, not its three-letter extension--this makes labeling files easier.
Also giving old-time Mac users a reason to be happy is the addition of spring-loaded folders to the Dock. If you have a folder with subfolders in the Dock, you can drag an item to the folder's icon in the Dock and hold it there, and the folder will open. You can then continue navigating down the folder's hierarchy until you see where you want to drop the item.
The Finder Help menu gets a strange cosmetic makeover but also adds a little bit of functionality; instead of just referring you to the Mac OS X Help Viewer, the Help function can step you through some basic tasks. And Spotlight adds Boolean logic: you'll be able to search for "spot" and "dog" not "light."
One of the previously revealed features includes easier widget construction, such as the integration of a Safari clipping widget for Dashboard. Once you have a favorite Web site loaded in Safari, one click of a button calls up Dashboard, with the Web Clip widget displaying the page. You can position the page, clipping off uninteresting parts, and choose a frame style; when the page is updated, the Web Clip widget also updates live. This way you can have a selection of must-see Web pages available with the instant ease of calling up Dashboard.
Of all the end-user changes in Leopard, the one most likely to attract Linux users is Spaces. This multiple desktop feature was previewed publicly, but it wasn't explained well. Switching between desktops and dragging windows or applications from one to another is very intuitive--a good example of how Apple takes an idea and makes it better.
The final release of Mac OS X 10.5 Leopard will happen in spring 2007.