SAN FRANCISCO — Apple Inc. CEO Steve Jobs took the wraps off a revamped line of iPods on Tuesday and trumpeted a truce with NBC Universal that means the TV network will begin selling programs again on iTunes.

The product announcements were largely expected, and investors were less than energized by the news, sending Apple's shares down $4.96, or 3.1 percent, to $152.96 in afternoon trading.

The iPod upgrades Jobs revealed Tuesday in a theater in San Francisco include two slick new Nano models, oval-shaped devices that Jobs said are the thinnest iPods Apple has ever made. A $149 version comes with 8 gigabytes of memory; a 16-gigabyte version is $199.

The new models represent the incredible appetite for iPods — Jobs said Apple has sold 160 million iPods since their introduction. But Apple has to work hard to differentiate them from the iPhone, Apple's cell phone/iPod/Internet device that threatens to cannibalize some of the demand for iPods.

Jobs also showed off three new versions of the iPod Touch, the closest cousin to the iPhone. An 8-gigabyte version of the new model will sell for $229; a 16-gigabyte version will be $299 and a 32 GB model will be $399.

In the deal with NBC, the television network is coming back to iTunes, a year after pulling out in a dispute over the prices Apple charges for shows it sells on the online service. At that time, NBC Universal-controlled television programming made up an estimated 40 percent of the video downloads on iTunes.

Appearing thin but energetic, Jobs kicked off the event by flashing a snarky message on a screen behind him: "The reports of my death are greatly exaggerated."

Jobs played off a famous line from Mark Twain in referring to obituary preparedness on him that was accidentally posted by Bloomberg News and then retracted. News outlets regularly prepare obituary material on famous people.

Questions about Jobs' health swirled after he appeared gaunt at a recent Apple event. Apple has since said Jobs, 53, a survivor of pancreatic cancer, suffered from a bug and is better.