AP

Steve Jobs demonstrates the MacBook Air notebook computer.

One week after the big Consumer Electronics Show in Las Vegas (which we discussed last week), San Francisco becomes America's high tech mecca.

It's Macworld Expo, the showcase for new and exciting stuff from Apple. While this year's blockbuster was a notch or two down from last year's iPhone, I still think I want one.

"This is the new MacBook Air, and you can get a feel for how thin it is," said Apple CEO and chief evangelist Steve Jobs, who had the crowd at San Francisco's Moscone Center drooling over the svelte notebook computer he was holding.

What's billed as "the world's thinnest notebook" weighs just three pounds and is a wispy 3/4 of an inch thick—not much bulkier than a padded envelope.

Jupiter Research analyst Michael Gartenberg gushes that the Air is the "technology object of desire for 2008. This is the one that people are going to want."

Even the $1,800 base model MacBook Air is generously appointed with 2 gigabytes of RAM, an 80-gigabyte hard drive and a 13.3-inch screen with 1200-by-800 resolution. Apple claims that even with its slimmed-down battery pack, the Air will endure for five hours before you have to plug it in.

Of course, the form factor does necessitate a few compromises. There's no built-in DVD drive (an external model is available, but new "Remote Disc" technology lets you wirelessly link to the drive of a nearby Mac or Windows computer ); and there is only one USB port (you'll need an external hub to hook up a mouse AND a printer).

Sound like something you'd like? You can pre-order a MacBook Air now; Apple says you'll have it in two to three weeks.

Also at Macworld, Jobs announced that Apple's popular online iTunes service now rents digital movies, and he has all the major studios behind the venture.

iTunes movie rentals are $3.99 for new releases and $2.99 for older titles ($1 more if you want to view a high definition version).

Renting a movie lets you store it for up to 30 days on your computer or iPod; once you start viewing it, you've got 24 hours to watch it as much as you want before it disappears.

There's another option for viewing iTunes movies: The Apple TV box, a product introduced a year ago and now offered at the reduced price of $229. It is designed to reside unobtrusively in your living room, supplying entertainment to your widescreen television.

New software (also available to existing Apple TV owners) lets the box download directly from an Internet connection; the original implementation required a wired or wireless connection to a computer.

But while Apple TV is versatile (you can also use it to play back music and photos on your television), you can't use it like a VCR or a TiVo to record TV shows for time-shifted playback.

At least not yet.

Some observers were disappointed that Jobs failed to introduce a new and improved version of the wildly popular iPhone at Macworld, but he did unveil new software that will let users customize their home screen and even figure out where they are on a map without using GPS (global positioning satellites). Instead, it uses wireless Wi-Fi signals and cell phone towers to pinpoint your location.

"We triangulate the beacons, look in their database, and it tells us where we are," Jobs said. "Isn't that cool?"

That is cool, but if you don't have an iPhone, try Google Mobile Maps on your handset. It uses the exact same technique to pinpoint your location.

GMM is totally free, although you'll want to have an unlimited data plan for your cell phone because it downloads maps as you move, and that can gobble up a lot of bandwidth.

Watch Computer Corner every week on News 8 Midday at noon (usually seen on Wednesdays), or online any time.

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