In Depth Mac OS X Leopard Review

ArsTechinca's John Siracusa posts an in depth review of Leopard, which refreshingly goes beyond the typical superficial glance at features. In fact, portions of the review may be too technical for the many readers, but does point out several under-the-hood improvements in Mac OS X 10.5 that may not be immediately obvious. Indeed, Siracusa summarizes the 17 page review:

As I've learned more about Leopard, it's become increasingly clear where, exactly, those two-and-a-half years of development time went. Leopard is absolutely packed with improvements. It seems that not a corner of the OS has gone untouched.

Perhaps that's not as clear to the casual user who just sees the surface changes and the major new features in Leopard. But even in that case, there's more than enough to recommend it. if you're wondering whether you should upgrade to Leopard, the answer, as it's been for every major revision of Mac OS X, is yes.

That being said, the review does touch on some aspects of Leopard's superficial changes, including the new standardized look of windows, changes in Finder behavior and the impracticality of Apple's current Stacks implementation:

There's just not enough room in a single Dock tile for a stack of icons to convey any meaningful information. Only the top one, two, maybe three items have any visual impact. And those few items may be misleading (e.g., the home folder appearing to be the Desktop folder) or completely generic (e.g., the Pictures and Movies folders showing up as plain folder icons.) Seriously, Apple, this is a bad idea.

Siracusa is, however, enthusiastic about Time Machine ("people will actually use") and describes steady and significant improvements in Mac OS X's performance and responsiveness. Leopard's kernel is also said to be better about scheduling processes, allowing you to make better use of multi-core CPUs.

Of technical interest, the article explores Leopard's implementation of DTrace to assist in debugging, the full transition to 64-bit, and the full adoption of Cocoa:

The last vestiges of the original Macintosh API are finally being put to rest. They've done their job and are being given a decent burial, I think. A slow, almost natural transition. Bugs will be fixed in the 32-bit Carbon APIs, of course, but no new features will be added. All new GUI APIs in Leopard and future Mac OS X releases will be added as Cocoa-only APIs.

This transition, of course, affects some of Apple's biggest developers (such as Microsoft and Adobe) who have a large library of Carbon code for their applications.

A lot of groundwork has also been laid towards implementing resolution independence, though even Apple's implementation across their own applications is thus far inconsistent. Full Resolution Independence support as a user-accessible feature is not expected until 2008. But this should allow Apple to introduce super-high-resolution displays and provide a consistent user experience.

The full review is worth reading if you have an interest in Mac OS X Leopard.

Popular Stories

iOS 26

iOS 26.2 Coming Soon With These 8 New Features on Your iPhone

Thursday December 11, 2025 8:49 am PST by
Apple seeded the second iOS 26.2 Release Candidate to developers earlier this week, meaning the update will be released to the general public very soon. Apple confirmed iOS 26.2 would be released in December, but it did not provide a specific date. We expect the update to be released by early next week. iOS 26.2 includes a handful of new features and changes on the iPhone, such as a new...
Google maps feaure

Google Maps Quietly Added This Long-Overdue Feature for Drivers

Wednesday December 10, 2025 2:52 am PST by
Google Maps on iOS quietly gained a new feature recently that automatically recognizes where you've parked your vehicle and saves the location for you. Announced on LinkedIn by Rio Akasaka, Google Maps' senior product manager, the new feature auto-detects your parked location even if you don't use the parking pin function, saves it for up to 48 hours, and then automatically removes it once...
Foldable iPhone 2023 Feature 1

Apple to Make More Foldable iPhones Than Expected [Updated]

Tuesday December 9, 2025 9:59 am PST by
Apple has ordered 22 million OLED panels from Samsung Display for the first foldable iPhone, signaling a significantly larger production target than the display industry had previously anticipated, ET News reports. In the now-seemingly deleted report, ET News claimed that Samsung plans to mass-produce 11 million inward-folding OLED displays for Apple next year, as well as 11 million...
AirPods Pro Firmware Feature

Apple Releases New Firmware for AirPods Pro 2 and AirPods Pro 3

Thursday December 11, 2025 11:28 am PST by
Apple today released new firmware designed for the AirPods Pro 3 and the prior-generation AirPods Pro 2. The AirPods Pro 3 firmware is 8B30, up from 8B25, while the AirPods Pro 2 firmware is 8B28, up from 8B21. There's no word on what's include in the updated firmware, but the AirPods Pro 2 and AirPods Pro 3 are getting expanded support for Live Translation in the European Union in iOS...
iOS 26

15 New Things Your iPhone Can Do in iOS 26.2

Friday December 5, 2025 9:40 am PST by
Apple is about to release iOS 26.2, the second major point update for iPhones since iOS 26 was rolled out in September, and there are at least 15 notable changes and improvements worth checking out. We've rounded them up below. Apple is expected to roll out iOS 26.2 to compatible devices sometime between December 8 and December 16. When the update drops, you can check Apple's servers for the ...
AirTag 2 Mock Feature

Apple AirTag 2: Four New Features Found in iOS 26 Code

Thursday December 11, 2025 10:31 am PST by
The AirTag 2 will include a handful of new features that will improve tracking capabilities, according to a new report from Macworld. The site says that it was able to access an internal build of iOS 26, which includes references to multiple unreleased products. Here's what's supposedly coming: An improved pairing process, though no details were provided. AirTag pairing is already...
iOS 26

Apple Seeds Second iOS 26.2 Release Candidate to Developers and Public Beta Testers

Monday December 8, 2025 10:18 am PST by
Apple today seeded the second release candidate version of iOS 26.2 to developers and public beta testers, with the software coming one week after Apple seeded the first RC. The release candidate represents the final version iOS 26.2 that will be provided to the public if no further bugs are found. Registered developers and public beta testers can download the betas from the Settings app on...
iPhone 14 Pro Dynamic Island

iPhone 18 Pro Leak Adds New Evidence for Under-Display Face ID

Monday December 8, 2025 4:54 am PST by
Apple is actively testing under-screen Face ID for next year's iPhone 18 Pro models using a special "spliced micro-transparent glass" window built into the display, claims a Chinese leaker. According to "Smart Pikachu," a Weibo account that has previously shared accurate supply-chain details on Chinese Android hardware, Apple is testing the special glass as a way to let the TrueDepth...
maxresdefault

iOS 26 Code Leak Reveals Apple Smart Home Hub Details

Thursday December 11, 2025 4:02 pm PST by
Apple is working on a smart home hub that will rely heavily on the more capable version of Siri that's coming next year. We've heard quite a bit about the hub over the last two years, but a recent iOS 26 code leak provides additional insight into what we can expect and confirms rumored features. Subscribe to the MacRumors YouTube channel for more videos. Macworld claims to have access to an ...
studio display purple

Apple Studio Display 2 Code Hints at 120Hz ProMotion, HDR, A19 Chip

Thursday December 11, 2025 4:19 am PST by
Apple's next-generation Studio Display is expected to arrive early next year, and a new report allegedly provides a couple more details on the external monitor's capabilities. According to internal Apple code seen by Macworld, the new external display will feature a variable refresh rate capable of up to 120Hz – aka ProMotion – as well as support for HDR content. The current Studio...