Appleis Leopard is the sixth major version of Mac OS X, so Appleis challenge was to make the upgrade compelling, according to David Pogue at the New York Times. Time Machine is one of those items.

Perhaps Microsoft had an easier task with Vista. In that case, everyone knew what Vista needed: better security. In Appleis case, with Leopard, the company had to make sure users understand why they need Leopard.

While listing over 300 new features is nice, some of them fall into the category of a "Word of the Day" screen saver, so thatis not enough.

"The one Apple extols the most, with reason, is called Time Machine. It’s a backup program," Mr. Pogue wrote. "Of course, the world is full of backup programs. But almost nobody uses them. Chances are extremely good that you, at this moment, do not have an automated, regular backup of your entire computer."

Apple has made Time Machine not only painless and essential, but made it compelling as well with an eye-catching star field animation. Itis Appleis way to persuade people to use it.

Another compelling feature of Leopard is enhanced parental controls, which play catchup with Vista. "Now you can set time limits for your children’s computer use (different for weekdays and weekends), and even make the Mac lock itself at bedtime. A log tracks their activities, including e-mail and chat correspondents and Web sites visited."

There were several small gotchas, and some applications will have to be updated for Leopard. Windows users will be amazed at the installation: No serial numbers, no activation, and Leopard will install on high end Macs that are six years old.

"Leopard is powerful, polished and carefully conceived. Happy surprises, and very few disappointments, lie around every corner," Mr. Pogue concluded. "This Leopard has more than 300 new spots — and most of them are bright ones."