In addition to unveiling the new iPods, Jobs announced that NBC shows are once again available at the iTunes store and said that iPhone and iPod touch users have downloaded more than 100 million applications from the company's Apps Store since its debut 60 days ago. Jobs also announced the availability of iTunes 8, which includes a "Genius" feature that uses information from users to generate song playlists.

Since the original iPod was introduced in 2004, more than 160 million have been sold, Jobs said. Citing statistics compiled by market researcher NPD Group, Jobs said the iPod owns a 73.4 percent share of the U.S. music player market. Through iTunes, Apple offers more than 8.5 million songs and is the No. 1 distributor of music in the U.S., Jobs said.

Jobs said the new iPod nano is the thinnest iPod ever. The product is oval shaped, designed with curved aluminum and glass, and is available in nine colors.

Taking a cue from the iPhone, the new nano also uses an accelerometer which automatically orients the screen and switches between various views as the device is rotated. The new nano offers battery life for up to 24 hours of music playback or four hours of video playback and is available in 8- and 16-GB models, priced at $149 and $199, respectively.

The second generation iPod touch is thinner, also, but offers the same 3.5-inch widescreen display as the original, Jobs said. It also offers 802.11 b/g Wi-Fi wireless networking, integrated volume control buttons, a built-in speaker, a built-in accelerometer and other advanced sensors. The new iPod touch is available for $229 for an 8-GB model, $299 for the 16-GB model and $399 for the 32-GB model, he said.

Jobs talked at length about the Genius feature, which he said, "Helps you make great playlists that you probably wouldn't think about making." A Genius sidebar appears in iTunes and recommends users purchase additional songs based on their library and musical preferences. The Genius feature is also built into to the new iPod class, iPod touch, and iPod nano.

Jobs announced that Apple is now offering a 120-GB iPod classic for $249, the same price that the company previously charged for an 80-GB model. Apple also discontinued the "thick" iPod Classic and now offers only the slim line model, Jobs said.

"We started off with putting 1,000 songs in your pocket. You can now put 30,000 songs in your pocket," Jobs said of the expanded storage space.

Jobs got some laughs to open the event by showing a slide that said, "The reports of my death are greatly exaggerated," a humorous reference to a recent Bloomberg snafu in which his obituary was briefly posted on the Internet. Recording star Jack Johnson performed at the event following the presentation by Jobs.