Speaking at Apple’s music event, CEO Steve Jobs, in his first public appearance since his medical leave of absence, introduces iTunes 9. After noting that iTunes is the largest music store in the world, boasting some 100 million accounts, Jobs rattles off some of the software’s new features. Among them: Genius Mixes and improved synching. The latter enables more specific synching and supports a new way of managing applications for the iPhone and iPod touch with a nice drag-and-drop feature. Very easy to organize and reorganize applications. The crowd really likes this one.

Also included in this update: Home Sharing, which allows songs, movies and TV shows to be shared and copied to up to five home computers. Another very slick feature that allows users to simply drag and drop songs between computers to copy them.

iTunes 9 also features a new store with redesigned music, movie, TV pages and a handy new navigation bar. Beyond this, there’s also support for Twitter and Facebook.

“You know, some of us here are old enough that we actually bought LPs,” says Jobs. “You used to get liner notes, essays and photos, but that stuff left us when we moved to digital music.”

With that, Jobs announces iTunes LP–the official name of the company’s rumored “Cocktail” album bundle. As expected, these iTunes LP bundles will feature additional art, photos and whatnot. Apple is working directly with artists and labels to develop them.

A Doors “LP” is offered up as an example and it includes some videos exclusively recorded for iTunes–Ray Manzarek talking about how Jim Morrison named the Doors (“Not a door-door, man. Like the door in your MIND.”). Surprisingly nice little video, actually. Certainly, it’s likely to appeal to die-hard fans.

Apple (AAPL) is doing something similar with movies–iTunes extras. Movies bundled with additional photos, etc.

Live from Apple’s “Let’s Rock” Event

• iPod Updates, Games, Nano Video Cameras
• iTunes 9, iTunes LP, Home Sharing, Genius Mixes
• Steve Jobs: “I’m Vertical, Back at Apple and Loving Every Day of It”
• Event Photos by Adam Tow

Next up on the Macworld agenda: iMovie. This Apple (AAPL) software has been given not just a refresh, but a full rewrite. We’ve added so much to iMovie this year, says Phil Schiller, that iMovie will be the consumer video editing software to have. And that may turn out to be so. Precision editing, drag and drop. Dynamic themes. Automatic stabilization. Animated travel maps. Randy Ubillos, Apple’s chief architect of video, takes the stage to demo the product.

He quickly demonstrates the optimization of a video clip, adjusting its audio, the angle of the video. It’s a very complex edit and he does it very, very simply. The video stabilization tool is, and I hate to sound like a fanboy here, mind-blowing at first look. It’s accurate and fast, and appears to be professional or near-professional in quality. Furthermore, these enhancements are for the most part being done in real time.

A set of new built-in animations, transitions and themes rounds out the application. All very slick.