Ending months of speculation and hype, Apple was expected Wednesday to unveil a tablet computer it hopes will rival the popularity of the Macintosh computer, iPod and iPhone.

Apple chief executive Steve Jobs is expected to take the wraps off the long-awaited device at San Francisco's Yerba Buena Center for the Arts Theater at an event scheduled to start at 10:00 am Pacific time (1800 GMT).

With trademark secrecy, the Cupertino, California-based Apple has declined to officially release any information about what it described in the invitation to Wednesday's event as its "latest creation."

According to press reports, Apple plans to unveil a tablet computer known as the iPad or iSlate that would cost anywhere from 600 dollars to 1,000 dollars.

It will have a 10-inch (25.4-cm) color touchscreen and wireless connectivity for browsing the Web and downloading music, movies, TV shows and mini-programs known as applications which have been a smash success on the iPhone.

The tablet is also expected to function as an electronic reader for books, newspapers and magazines, posing a challenge to other e-readers on the market such as Amazon's Kindle, but offering a lifeline to struggling publishers.

A tablet would be Apple's first major product release since it came out with the iPhone three years ago and technology analysts stressed that the hardware is not as important as the content available for the device.

"Amazon may have won the e-book reader battle, but the war is about far bigger things," said Canada-based independent technology analyst Carmi Levy. "It is about a device that can do many things as you bring your digital content with you.

"The irony is that it is no longer about hardware, it is about services that connect to the hardware," Levy said. "The iPod was just a media player but what made it special was iTunes and the online App Store."

An Apple tablet would likely synch with iTunes and the more than 100,000 applications at the App Store.

It may also have ties to the largest US bookstore chain, Barnes & Noble.

Barnes & Noble shares soared 13.35 percent on Wall Street on Tuesday following a report by technology blog TechCrunch that a Barnes & Noble bookstore would be built into the Apple tablet.

Apple has also reportedly been in talks with leading newspaper and magazine publishers about making digital versions of their publications available for the device.

Not all analysts are convinced that Apple, which announced a record quarterly net profit of 3.38 billion dollars on Monday, has a winner on its hands with a tablet computer.

Tablets are too large to serve as mobile devices and too small to compete with desktop and laptop computers.

"The real question is what will people do with an Apple tablet that they can't do pretty well on some other device?" said NPD Group analyst Stephen Baker. "Anyone that has tried this has failed."