Apple chief executive Steve Jobs, who underwent a liver transplant five months ago, made his first public appearance Wednesday, taking the spotlight in an event to introduce the company's new iPod lineup.

Thin but appearing healthy, Jobs came on stage to a standing ovation by many of the reporters, analysts, and Apple employees gathered in San Francisco to hear the company's latest product announcements, the biggest of which was a new iPod Nano with a built-in video camera.

However, Jobs stole the show. His appearance ended weeks of speculation as to whether the tech icon and Apple co-founder would continue his role as star pitchman for the consumer electronics company.

Wearing his usual black turtleneck and jeans, Jobs played emcee to the event, letting other company executives demonstrate the new products. Before launching the event, Jobs thanked the organ donor who saved his life.

"I now have the liver of a mid-20s person who died in a car crash and was generous enough to donate his organs," Jobs said in encouraging others to become organ donors.

Jobs also thanked Apple chief operating officer Timothy Cook and the rest of the executive team that ran the company in his absence. "They really rose to the occasion and ran the company very ably in that difficult time."

Nevertheless, Jobs said he was happy to return to work. "I'm vertical and back at Apple, loving every day of it."

Jobs gave no indication whether he would continue to lead Apple's major news events in the future. However, he is expected to be fully involved in product development. The CEO underwent a liver transplant while on medical leave in the first half of the year. No reason was given for the surgery, however, industry observers believe it's related to complications that arose several years after his 2004 surgery for pancreatic cancer.

Product announcements at the event were far less than the speculation that had been swirling around the Web for many weeks.

Many industry observers had expected Apple to add a built-in video camera and microphone to the iPod Touch, which would have taken the pocket computer and media player closer to Apple's iPhone in features, but without the cellular connection. Instead, Apple chose only a minor refresh to the Touch and added the camera to the company's popular Nano. Apple has sold 100 million Nanos since introducing the device in September 2005.

In unveiling the new Nano, Jobs compared it to the Flip, a popular portable video camera from Pure Digital Technologies, which Cisco acquired this year for $590 million in stock. In a nod to the success of the Flip among casual video takers, Jobs said, "This market is really exploding and we want to get in on this." Apple is adding the video recorder without changing the size of the slim device that easily fits in a shirt pocket. However, Apple has increased the size of the Nano's screen to 2.2 inches. In addition, the new Nano has a built in microphone and an FM radio.

Despite the new features, Apple did not raise the price of the device. The 8-GB model will cost $149 and a 16-GB version $179. The new Nano was available as of Wednesday in eight colors.

Apple lowered the prices on other members of the iPod family. The starting price of the iPod Touch went to $199 from $229 for the 8-GB model. Apple also doubled the storage in its other models while keeping the prices about the same. The new 32-GB model costs $299 and the 64-GB version is $399.

Apple also increased the storage of the iPod Classic, the only iPod with a hard-disk drive, to 160 GB from 120 GB, while keeping the price at $249. Many Apple watchers had expected the company to discontinue the Classic.

Finally, Apple doubled the storage of the basic iPod Shuffle to 2 GB and increased the price to $59 from $49. In addition, the company introduced a polished stainless steel model with 4 GB of storage for $99.

Apple is refreshing the iPod line in time for the holiday shopping season, the biggest shopping time of the year. iPod sales have slowed considerably as the market for portable media players has matured. In July, Apple reported that sales slid during the quarter ended June 27 by 7% from the same period a year ago to 10.2 million units.

Apple also refreshed the iTunes store that works with the iPod line, as well as the iPhone. Among the new features in iTunes version 9 is more content added to the purchase of albums. Along with the songs, Apple is adding original album covers, video of interviews with artists, liner notes, lyrics, and any other content provided by record companies and musicians.

By offering such content without increasing the price of albums, record companies are hoping to boost sales at a time when people are buying more individual songs for far less, hurting profit margins.

Apple also made it easier to share links to music on the iTunes store on social networks Facebook and Twitter, and also added features to simplify organizing applications purchased from Apple's App Store on the iPhone and iPod Touch.

Apple unveiled an upgrade to the iPhone and iPod Touch operating system. Version 3.1 includes bug fixes and extends Apple's Genius technology for discovering new music to applications. Genius is used on iTunes to recommend music on the iTunes store, based on music in a person's library. With the new version of the OS, the same feature will be extended to applications on a person's iPhone. Apple's App Store is accessed through iTunes.

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