As expected, Apple has officially confirmed that it will host a music-themed event next Wednesday, September 9, at the Yerba Buena Center for the Arts in San Francisco. An invitation sent out to media outfits and blogs today suggests the gathering will be iPod-related (just like in previous years) and references a classic Rolling Stones lyric with the typical iPod ad silhouette stating "It's only rock and roll, but we like it."

The Cupertino-based company has hosted a new product introduction of its iPods every September for the past few years, and this year doesn't look to be any different. Apple is expected to introduce new versions of its iPod nano and iPod touch featuring cameras and (at least on the latter) a microphone; transforming the touch-enabled media player into a nifty VoIP phone wherever a Wi-Fi connection is available.

Besides new iPod models Apple may also discuss a new interactive album format, known as Cocktail, and could possibly introduce a new version of iTunes with social networking features. Some expect an Apple tablet to be announced as well, which perhaps isn't too far-fetched considering the slew of rumors and 'evidence' on the company's own software, but this seems rather unlikely for now - most are betting on a release early 2010.

Last but not least, the September 9 date has also fueled rumors that The Beatles' discography could finally make its appearance on iTunes. That Wednesday is the same day the band's remastered digital albums and Rock Band video game will be released. Whatever Apple has in store, we'll be filling you in with the details next week.