Despite the easy availability of pirated music, most U.S. kids in the 9-to-14-year-old “tween” bracket are now paying for at least some of their music downloads.

That’s the key finding of “Kids & Digital Content,” a survey issued Wednesday by the NPD Group. According to NPD, 70% of U.S. tweens download digital music in an average month. Among them, nearly half (49%) used Apple’s (AAPL) iTunes to get their songs and 16% used MySpace (NWS).

However, the second most popular source of digital music, used by more than a quarter (26%) of the group, was the peer-to-peer file-sharing service Limewire.

“The recording industry has focused on high-profile litigation programs as a deterrent, and education initiatives to communicate alternatives to illegal music file sharing,” said NPD vice president Russ Crupnick. “Findings in this report suggest that the industry can still do more to promote specific ways children can obtain digital music legally, through pre-paid accounts and gift cards.”

Of course, all this assumes that the 3,376 kids who sent in completed surveys told the NPD the truth, not what they thought the survey group wanted to hear.

There are few things Steve Jobs loves more than a dramatic Macworld surprise announcement, but three weeks before his annual keynote speech, someone - my guess would be Rupert Murdoch - just stole his thunder.

Several sources this morning - including the Financial Times and the Wall Street Journal - are reporting that Apple (AAPL) and News Corp. (NWS) have struck a deal for a new video-on-demand service that could change the way digital movies are distributed, viewed and paid for.

Citing an unnamed “person familiar with the situation,” the FT reports that the two companies signed an agreement that would allow customers to download the latest 20th Century Fox movies through the iTunes store and watch them for a limited time. No pricing details were available, but earlier reports suggested that Fox and Apple were talking about charging $2.99 for 30 days viewing. That’s considerably cheaper than competing services from BlockBuster and NetFlix, neither of which work with iTunes, Macs or iPods.

In addition, Apple is reportedly extending its FairPlay digital rights management system for the first time to another company’s product. As part of the same deal, Fox will sell its new releases on FairPlay DVDs that permit customers to transfer, or “rip” the content to a computer or video iPod. As the FT points out, there is software available to rip movies today, but using it is considered piracy and can land you in jail.

Disney is the only other studio that makes new releases available on iTunes, but only to buy, not to rent. Paramount, Metro-Goldwyn-Mayer and Lionsgate sell older library titles. But the tide may be turning, and Apple is reported to be in talks with Sony, Paramount and Warner Brothers.

“Fox and potentially other ­studios are coming around to the idea that there is nobody out there to challenge iTunes,” Jonathan Weitz, a principal with IBB Consulting, told the FT. “This deal is a sign that media mobility is coming to the mainstream.”

The best instant analysis of the deal this morning is on Silicon Alley Insider, where Dan Frommer seems to have stayed up all night trying to work the angles. See his winners and losers column here and his six questions here. Among the latter, our favorite is No. 6:

How will Blockbuster, Amazon, Netflix, Microsoft, Sony, cable, telco, and cellphone companies, and other rivals respond? Apple’s iPod line dominates the portable media player market, and the iPhone is taking a big chunk of the smartphone market. And now, it appears, there will finally be digital rentals compatible with Apple’s gadgets. Surely Jobs’ rivals haven’t been sitting around doing nothing. How will they fight back? Lower rental prices? More portability/less DRM? This should be a fun one!

Two developments in the wake of NBC Universal’s (GE) weekend exit from Apple’s (AAPL) iTunes store:

Ruport Murdoch’s Twentieth Century Fox (NWS) is reported to be “actively negotiating” with Apple to put new releases and catalog titles on iTunes beginning in early 2008. According to Rich Greenfield at Pali Research (link; activation required) several things have changed to break the deadlock, including growing levels of movie piracy and new flexibility on Apple’s part in terms of pricing. Greenfield’s casual speculation that Apple might be willing to charge $15 per movie download has triggered some interesting analysis (see AppleInsider and Ars Technica’s Infinite Loop) but should probably not be treated as gospel.

NBC Universal CEO Jeff Zucker placed his company’s digital strategy last on his list of priorities in a luncheon speech at the UBS Global Media & Communications Conference on Monday. Repeating an earlier claim that NBCU’s deal with Apple was worth “only $15 million” in profit, he added: “That’s nothing to sneeze at, every dollar matters. But it wasn’t the game changer for us that it was for Apple.” He pointed to NBC’s video offerings on Amazon and NBC Direct and singled out for praise hulu.com, its joint effort with News Corp.:

We’re in the beta test with Hulu and we have 60,000 users, seven major advertisers. The online press wanted to kill it, but it’s doing well. Advertisers tell us they want a safe environment. That’s what this is about. They don’t want a cat on a skateboard, but they do want The Simpsons or a film they like. (see Paid Content’s report here)