Apple OS X Snow Leopard: Big cat or big patch?

Operating system

By James Sugrue / Tuesday, October 27 2009

What would life be without great rivalries? Liverpool vs. Manchester United in football. New Zealand vs. Australia in anything. And in the computer world, Apple vs. Microsoft. With both companies releasing new versions of their operating systems this year, that rivalry is again at the forefront. As this is a PC magazine, which, let’s face it, to most people means Windows, most of you will be more interested in Windows 7, but it’s always good to know what the opposition is up to. But be warned, if you own a Mac with a PowerPC CPU, Apple doesn’t want to know you, this upgrade is for Intel Macs only.

What’s new?
When you first boot into Snow Leopard it’s hard to tell the difference between it and Leopard. The first obvious visual difference is the way Stacks looks. Under Leopard it was white, whereas under Snow Leopard it is translucent black and hides some nice new tweaks. The best of which is the ability to scroll through a stack and navigate its directory structure forward and back.

Expose is now integrated into the dock so you can click and hold an application icon in the dock, and Expose will show all the windows for that application, with minimised windows showing as smaller icons below the open windows. You can also tab between application windows in Expose.

The finder has been completely rewritten for Snow Leopard. It uses the newer Cocoa programming libraries, which allow it to take advantage of new technologies in the OS, such as 64-bit support and the new Grand Central Dispatch (more later). Seat of the pants benchmarking suggests a snappier and altogether more responsive Finder. Rendering icons seems quicker under Snow Leopard than under Leopard, for example. You can also save common Spotlight searches to the Finder Sidebar – for example, .doc files created this week, or all files larger than 3GB.

While we’re talking about searching, Spotlight now indexes Faces and Places from iPhoto. Now you can search for photos by place or person. Typing in “Steve Jobs” would show all photos of "the" Steve, and typing “Timaru” would show all photos you had in your collection from the Riviera of the south.

The next feature upgrade is probably something most Mac owners have never used – the Services. Services are “applets” that allow you to tap into special features of the operating system or send information between applications. For example, you can highlight some text and have it converted to another language, or have the speech processor say it to you. Under Snow Leopard Services has been completely revamped and now allows customisation through Automator. Services also now filters options relevant to the content selected. You can, for example, highlight a word and click the Services menu in the menu bar (or right click) to see options such as, Look up in Google, Add contact, New email with selection and Look up in Dictionary.

New QuickTime
Snow Leopard also introduces a new version of QuickTime – called QuickTime X. QuickTime no longer has a free and Pro version – it’s all in the same package that comes with the OS. You can now capture video or audio, take a screen capture, trim video, reformat for iTunes and publish video to YouTube right from within the standard QuickTime. QuickTime X introduces a new user interface that fades out the controls when not in use, and also hides the surrounding window border to allow focusing on the video content rather than the window. Apple also claims a performance increase of up to 2.4x in the latest version, and smoother playback of HD content. I can’t confirm or refute those claims, but in testing on a number of systems, all video I threw at each system played smoothly and stutter free, and QuickTime itself loaded much faster than the previous version. QuickTime will now also offload decoding of H.264 video to the Graphics Processor found in most new Macs, which allows for smoother playback and frees the CPU for other tasks.

Improved Preview
When I first switched to the Mac platform a few years ago the app that impressed me the most was Preview. The ability to quickly and easily view images and PDFs, and have it as a first class citizen in the OS was a boon to me. In Snow Leopard, Preview has a number of compelling improvements. The biggest for me is the intelligent text selection feature with PDF documents. Previous versions made it difficult to select text across columns, or if there were embedded images, but now Apple uses “advanced artificial intelligence to analyse each PDF document to understand the structure of its words, paragraphs, columns, and visual layout and creates a map of the document’s organisation”. This map helps Preview target the text you really want.

Other improvements
There are a number of little improvements that aren’t worth going into too much detail about, but that add up to make a nicer experience for the user. These are: faster shutdown and wake-up, faster time machine backup, improved colour gamma, a new thesaurus, minimise to app icon in the dock, date in the menu bar, and built in support for Exchange 2007. Plus much more, including a new version of Safari and iChat enhancements.

Top two
Somehow I’ve gotten this far into the review without mentioning the two major features of Snow Leopard. These are Grand Central Dispatch (GCD) and OpenCL. These two technologies are hidden from the end user but will, in time, make Snow Leopard a much faster and more compelling OS. The built in Apple apps use both, but it won’t be until developers recode their apps to use GCD and OpenCL that the average user will notice any difference.

So what are these two great features? GCD is a technology that allows the operating system to make full use of the multi-core processors in Intel-based Macs. Previously, developers had to make arbitrary decisions about how their app would perform and how it could balance the load across processor cores – most didn’t bother, and even if they did, they had no way of knowing how it would interact with the rest of the system. Under GCD the operating system takes the heavy lifting away from the developer and makes it easier to program for multi-cores.

OpenCL is a little easier to understand. OpenCL allows developers to take some of the heavy processing away from the CPU and let the graphics processing unit do the work, as it is idle most of the time. This allows the CPU to handle other tasks and lets the GPU unleash some of its power on processing other than graphical rendering.

All-in-all, Snow Leopard is about the sum of its parts. There is no one compelling reason to upgrade, but every (Intel) Mac owner should.

More Software reviews