Incremental updates to Mac OS X traditionally have consisted primarily of bug fixes. Significant changes to existing features are saved for the major updates (Panther, Tiger, Leopard).

So when Apple let loose the much-anticipated 10.5.2 update to Mac OS X Leopard on Monday, changes to two features introduced with the release of Leopard in October pleasantly surprised many veteran Mac users.

One change is the addition of an option in the Desktop Control Panel to turn off the translucent menu bar at the top of the screen. Some Mac users detested this new feature because the patterns of desktop images could make menu items hard to read. It didn't bother me all that much, but it's nice to have the option to make the menu bar opaque again.

Apple also tweaked the Stacks feature, which allows users to click on special folders in the Dock and see the icons of its contents fan out across the desktop. Some users didn't like how the folder looked like a pile of icons with only the topmost icon identifiable. Not only that, but they disliked how the icons fanned out from the Dock. The more items, the harder the feature was to use.

Apple has addressed these complaints by offering choices. Control clicking on a Stack reveals several new options, such as making the Dock icon appear as a folder and setting the folder's contents to appear as a list. This works much better for folders with numerous items.

It's very un-Apple-like to alter fresh features in a version of OS X not six months old. Could it be that Apple has decided to listen to its users?

Other observations:

Mac Pro's Reboot on Wake From Sleep: Incremental updates sometimes fix other issues not noted in Apple's documentation. As have most other owners of the new Mac Pro, I had hoped the 10.5.2 update would fix the dreadful "reboot on wake from Sleep" problem.

After a day and a half and more than a half-dozen wake from Sleeps, I have not had an unexpected reboot.

However, reports on Mac forums indicate that other Mac Pro owners still are experiencing the issue even after upgrading to 10.5.2. Others owners also report unresolved problems with their graphics (which I thankfully have not had.) Apple needs to fix this soon. Its Mac Pro customers - those who have bought Apple's priciest hardware - deserve better.

Improved performance: One point of speculation that dates back to before the Mac Pros were announced was that the 10.5.2 update would contain optimizations designed to extract better performance from the new models.

I have run both the Geekbench and XBench benchmarking software on my Mac Pro since upgrading to 10.5.2. Given the variable scores I tend to get from these programs, it doesn't look as if this update has boosted performance. But the Leopard Graphics Update, which users can install only after installing 10.5.2, did improve my graphics scores noticeably in XBench's Quartz Graphics Test, which leapt from averaging in the low 200s to averaging in the mid-250s, a 25 percent increase.

To upgrade to 10.5.2: If you're running Leopard and haven't updated to 10.5.2, click on the Apple Menu and select "Software Update." After the Mac reboots, go back to the Apple Menu and repeat the process to obtain the Leopard Graphics Update. A word of warning: The 10.5.2 update weighs in at a bulky 343 megabytes, so a fast broadband connection will come in handy.