Number 10 on the list of Leopard enhancements is Time Machine, Leopard's automated backup technology. "We are all walking time bombs," said Jobs.

"Misplacing information, mistakenly deleting it, or worse. We want to solve these problems in such a simple way that everyone actually uses it."

With Time Machine, Jobs explained, you click on it, and it automatically backs up everything, either to a local hard drive or network server, wired or wirelessly -- so you can use a hard drive you have connected to a new AirPort Extreme Base Station, for example.

Using Spotlight's search capabiliities, you can "search back in time" for lost files, Jobs explained. You can preview the file with Quick Look to make sure it's what you want, restore it using a single click, or restore your whole Mac.

"The goal here is to build this in and make it so simple and automatic that people just use it," said Jobs.

All of the new features of Leopard are being given to developers attending this week's WWDC -- they can retrieve their preview copies after the keynote.

Taking another opportunity to fire some sarcasm at Microsoft, Jobs said, "We've got a basic version, which is going to cost $129. We've got a Premium version, which is gonna cost $129. We've got a business version, $129. We've got an enterprise version, $129. And we've got the ultimate version, we're throwing everything into it, it's $129. We think most people will buy the ultimate version."

One more thing -- Safari?
"One of the things we haven't talked about today is Safari," said Jobs. "There are now more than 18 million Safari users. And if you look at Safari's market share, it has climbed from 0 to 5 percent across the entire internet."

Showing the relative market share for other Browsers, Safari is solidly in third place, behind Microsoft Internet Explorer (with 78 percent) and Mozilla Firefox (with 15 percent). Other browsers are estimated at 2 percent. Apple hopes to grow Safari's market share dramatically, said Jobs.

"The Mac's market share is great, but we want to grow, and in order to do that, we have to create a version of Safari for Windows. And that's exactly what we have done," said Jobs.

Safari 3 works on Mac OS X, Windows XP, and Windows Vista, said Jobs. He showed some benchmarks that demonstrate Safari for Windows running twice as fast as Internet Explorer when loading Web pages and faster still with JavaScript.

"So what we've got is the most innovative browser in the world, but we've also got the fastest browser on Windows," said Jobs. It's twice as fast as IE, 1.6 times faster than Firefox 2, and features built-in Google and Yahoo search.

Apple is releasing a new public beta of Safari 3 for both Mac OS X and Windows today, said Jobs.