Apple’s (NSDQ: AAPL) addition of a music recommendation engine to iTunes this week will have brought a nervous gulp from those already in that space. One such, Peter Gabriel-backed TheFilter, saw fit to issue a press release last night, designed to differentiate its nascent offering from that of Steve Jobs. CEO David Maher-Roberts said he “genuinely welcomes” iTunes’ new Genius feature as validating his own offering, but argued TheFilter covers a wider selection of media sources, like video and Last.fm…

iTunes’ new feature recommends to listeners tracks that are similar to their current song, whether from their own library or iTunes Store. The threat to TheFilter: its own plugin must also piggyback iTunes. In theory, other sites - Pandora, Last.fm et al - face a similar challenge. Apple now has something of an advantage and, if it comes down to communicating the products to users, may win there, too… Whilst Apple says Genius finds “songs from your library that go great together”, The Filter explains it’s “derived from a branch of artificial intelligence called Bayesian mathematics” and uses “an evidence model to derive the similarity of items, a pick-list of items that are statistically relevant by order of probability”. Rock ‘n roll!

Staci adds: An interesting counterpoint from Wired’s Listening Post, which got a preview of Zune 3.0’s MixView due Sept. 16: “What we saw made iTunes’ simple Genius feature look like a blast from digital music’s past. While iTunes serves up a text list of recommended songs within your library and from the iTunes store, adding to the more basic recommendations its MiniStore feature used to make, Zune reinvented the recommendation concept by collapsing artists, albums and fans into the same recommendation engine, more accurately mirroring the way people think about music.” The app will work for non-Zune owners who have Windows. Granted, it’s a much smaller group of users than iTunes.

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