SAN FRANCISCO — The iPhone may be Apple’s most talked-about product, but on Tuesday Apple focused attention on its most dominant franchise: the iPod and the iTunes music and video store.

At an event here called “Let’s Rock,” Steven P. Jobs, Apple’s chief executive, announced an array of incremental changes to the iPod product line and iTunes, setting the company up for the holiday shopping season. Mr. Jobs unveiled new features and a svelte design for the iPod Nano, a cheaper, upgraded iPod Touch, and a new version of iTunes that can recommend music to buy based on the songs in a person’s music collection.

Mr. Jobs also announced that NBC, a division of General Electric, was bringing its television lineup back to iTunes, 10 months after the two parties clashed over how much flexibility NBC would have on the pricing of new NBC programs. Both sides now say they got what they wanted. Television shows from NBC and other networks will all cost $1.99 for standard video quality, and $2.99 for high-definition video quality. Older shows like “Kojak” will sell for 99 cents.

Jean-Briac Perrette, who runs digital distribution for NBC Universal, said that NBC would have liked even more options, but that Apple had given the network most of what it asked for.

“We are pretty comfortable that most of what we are doing will work within those three tiers,” Mr. Perrette said.

Mr. Jobs said in an interview that the resolution came through personal discussions with Jeff Zucker, the chief executive of NBC Universal. “We both knew we wanted to get this together, and our mutual customers wanted us to get this together,” he said. “They let us know, we worked it out, and everyone is happy.”

At the event, Mr. Jobs boasted of Apple’s dominant and growing share of the digital music market. But Apple is about to get some new competition. Next week, the social network MySpace, a division of the News Corporation, is expected to unveil a joint venture with at least three major music labels. The new service will sell music downloads without the copying restrictions imposed by so-called digital rights management software. Other than EMI, the major music companies have yet to make such restriction-free music available to Apple, which they see as overly domineering in the market for online music.

Mr. Jobs appeared unimpressed by the strategy, which he said “hasn’t seemed to work for them so far.” He added, “iTunes’ market share is just growing since they started this.”

Among the changes announced to the iPod line, the most significant was to the iPod Touch, which is similar to the iPhone in form but lacks the calling features or monthly subscription plan. The new device will cost $229, a $70 price cut that should make the device more appealing to mainstream buyers and expose them to Apple’s App Store and its thousands of games and other programs.

The news from Apple comes after an unusually tough summer for the company. Its MobileMe suite of online services was bedeviled by technical problems when it was introduced in July, and owners of the new iPhone 3G have reported difficulty in maintaining high-speed connections to the Internet. Mr. Jobs said Apple would release a software upgrade this Friday that should fix many of the iPhone problems.

Also, Mr. Jobs’s own health became a subject of intense discussion after he appeared unusually thin at an Apple developers conference in June. Mr. Jobs joked about that on Tuesday. When he took the stage, a message that appeared on the large screen behind him read, “Reports of my death have been greatly exaggerated.”

Apple shares slipped during the day, losing 4 percent to close at $151.68, amid disappointment that Mr. Jobs did not follow his usual practice of unveiling a last-minute surprise onstage.