Apple's new Macintosh operating system ships tomorrow. Visually stunning, OS 10.5--a.k.a. Leopard--is fast and stable, and it features a consistent set of powerful file-management tools familiar to anyone who has ever used iTunes. And unlike Microsoft Windows, which seems to grind slower with each successive release, OS 10.5 feels faster than 10.4 on the same hardware--provided that you have sufficient memory.
As I mentioned in my May 2007 review, Leopard's centerpiece technology is Time Machine, a revolutionary backup system that lets you take your computer "back in time" to find accidentally deleted files, address-book entries, photographs, and the like. Click "Time Machine," and the desktop drops off the screen to reveal a flowing star field with a sequence of windows progressing back toward the beginning of time (or at least to when you installed Leopard). Click on the timeline, and you can travel back to before you accidentally deleted a key paragraph in that annual report. You can then copy it and bring it back with you into the present.
Time Machine also has a clever disaster-recovery feature that lets you rebuild your Mac from a backup if the main hard drive fails. This feature is built into the MacOS installation process: once the operating system is installed, the computer asks you if you have a Time Machine backup to restore.
Yes, Time Machine's functionality is really no different than that of a traditional incremental backup system. But Time Machine is so much prettier and easier to use! Like the rest of 10.5, Time Machine's graphics and animations are smooth and pleasing but not excessive. The program needs just a tiny bit of configuration: turn it on and specify the hard drive where you want to keep your backups. The defaults are sensible but easily customized. And Time Machine is extensible, so that developers can incorporate it into their own applications. (For example, clicking the Time Machine icon while AddressBook is active allows you to restore individual address-book entries, rather than the entire AddressBook file.)
Unfortunately, Time Machine has a serious problem: there is no way (that I can find) to remove a file from a Time Machine backup. This is a pretty glaring omission. After all, Leopard has a "secure empty trash" feature that lets you throw away files so that they can't be recovered with forensic tools. What's the point of erasing a file on the hard drive and then overwriting the disk sectors seven times if Leopard is going to keep a copy of the file in the Time Machine backup?
Leopard's other big breakthrough is its Parental Controls, one of the best implementations of child-control technology I've seen. Parental Controls allows you to set time limits on your child's use of the computer (separate limits on weekdays and weekends), bedtimes, and wake-up times. The system gives a warning when bedtime is approaching; if your child is working hard on a paper for school, you can type in your username and password and lift the electronic curfew.
Parental Controls also allows you to specify websites that can't be accessed, the people with whom your child can exchange e-mails and instant messages, and even which applications your child can run. I was pleased to see that restrictions on websites and the like are actually built into the operating system, rather than built into Apple's Safari Web browser: I downloaded and ran a copy of Firefox, but the blocked websites remained blocked.
When your child tries to access a blocked website, the OS displays a polite message and offers to unblock it if one of the computer's registered adults provides a username and password. Leopard also logs the fact that one of the parental-control rules was violated. I'm not sure what a parent would do with this information, but it's there if you want it.
Aside from those two advances, most of the other Leopard improvements are little more than apple polishing. If you are a fan of the "smart folders" feature in iTunes, which lets you automatically see your top-rated songs or most recently played videos, you'll feel completely at home using the same feature in Apple's Finder, Mail Client, iPhoto, and other applications. These smart folders are also integrated with Apple's Spotlight desktop search: click the magnifying glass in the upper right-hand corner and type someone's name, and a new finder window will appear showing the mail messages, documents, and calendar and address-book entries that contain the name.
There are lots of other clever features sprinkled throughout 10.5. For example, Leopard now has a "Back to My Mac" feature that lets you set up your home computer so that you can remotely access its desktop and files, even if it's trapped behind a firewall (provided that you have paid your .Mac subscription fee). You can attach your Mac to an HD television set (all iMacs now feature DVI output) and use it to play DVDs. You can preview a file before you open it. You can create notes and to-do lists and store them in your mailbox (which means that they'll sync across multiple computers if you are using Exchange, IMAP, or .Mac to sync). And you can drag a bunch of files to a "stack" in the dock; we'll see if this is the cure for the cluttered desktop that befuddles so many writers that I know.
Leopard comes standard with all new Macs shipping today, but if you want that new-Mac experience for your existing hardware, it will cost you $129 for the single-user edition or $199 for the five-user Family Pack. You'll also need to spend $79 to get a copy of iLife '08 (also included with new Macs). Leopard works much better if you have a .Mac subscription ($99/year). I also recommend spending $79 for iWork '08 to get Keynote, Apple's superior alternative to PowerPoint. Yes, discounts are available on some of these items, but that's still more than $300 per year to keep your Mac up to date with Apple's latest software and services.
These products are all worth the money if you value having a computer that's fast and easy to use more than you value, say, 100 gallons of gasoline or dinner for four at a really nice restaurant. For me there's no question: I bought them all. But people who are thriftier than I would probably do better to hold off on this update.