As expected, Apple unveiled the latest upgrade of its Mac OS X operating system on Tuesday at the Seybold Conference and Expo in San Francisco, with an unexpected appearance by the company's chief executive officer. Apple President and CEO Steve Jobs, who was scheduled to speak via satellite from the company's Apple Expo in Paris this week, introduced the latest update to the operating system he called Apple's most "significant operating system overhaul since 1984." Jobs appeared live at Seybold after the Paris Expo was cancelled earlier this month following the terrorist attacks in the US. Apple started shipping the first version of the Mac OS X in March - version 10.0 - but it wasn't well received by users and analysts, because it lacked some key features and had bugs in it. But this upgrade attempts to remedy that situation. "This is the mainstream release," Jobs said. "We're beyond the early adopters." "This is a long term strategy, not just a quick release," Phil Schiller, Apple's vice president of worldwide product marketing, said. The updated operating system, which will be in stores on Saturday in the UK, brings features including DVD (digital versatile disc) playback and DVD burning to the "dock," which would be the Mac OS equivalent of Microsoft's Windows Start button. The operating system's upgrade also improves on its predecessor's performance and speeds up operations such as the launching of applications and resizing of windows, Schiller said. Meanwhile, Apple also added system status icons, similar to those in Windows, including audio, Internet connection details, and date and time details, to the toolbar. The company also took "plug and play" one step further, so that now when a user plugs in a USB (universal serial bus) printer, the operating system automatically recognizes the printer and begins printing any files in the printing queue, Schiller said. For the next three months, Apple will focus on applications, Jobs said. "There are already about 1,500 applications shipping for OS X," he said. "And more of the important applications we use every day are going to ship OS X-native in the next three months." One of those core applications is Microsoft Office, which will begin shipping in November, Jobs said. From Tuesday, OS X users can download a demo of Microsoft Word from Apple or Microsoft, Jobs said. "I think (Microsoft) could end up being the poster boy for what an OS X app should look like," he added. Microsoft took the wraps off of Office for OS X version 10.1 last week. Mike Evangelist, marketing and product manager with Apple, also gave a demonstration of Apple's second generation DVD burning software, iDVD2, which will be available from October. The software allows users to create a DVD that is playable on home DVD players. IDVD2 features enhancements over the previous version, giving users the ability to create motion menus, as well as include video and music in the background of the DVD menu. It also allows customization of buttons and text, as well as of objects in the background, Evangelist said. While the audience response was generally positive, one user said that while he was impressed by the applications shipping for OS X, the one he needed still wasn't available, keeping him with the older version for a while longer. "I was really impressed," said Robbie Fernando, a Web editor with Internet search company Ask Jeeves. "The applications that they introduced are really, really impressive." Fernando said he is still running Mac OS 9 because the main application he runs, Apple's video editing Final Cut Pro, is yet to be released for the new operating system. Another user was happy to hear more about the update to OS X, but thought Apple owed the operating system some new hardware to release its full potential. "I was kind of disappointed that there was no new hardware announced," said Doug Landry, a Web editor with the Mac enthusiast Web site Powerbook Zone. "10.1 is great but it really needs some new hardware." OS X version 10.1 will be available in stores from Saturday. The full version will cost £99, while the update CD will be priced at £14.99. Apple will also be offering free upgrades to current OS X users until October 31, 2001.