Genius Mixes

In addition to home sharing, another great iTunes 9.0 addition has been the "genius mix" function, which can be used straight from your iTunes library or taken on the road via an iPod.

What Apple has done with this function is collect data from 27 million users and their over 50 billion individual songs to determine as best they could which songs sound best with which other songs. So in my library that is very limited in 60s and 70s era british rock music it is very likely that choosing a song based on the Beatles will follow immediately with The Who since those are really the two bands whose catalogs I own that even remotely resemble one another. Here's a real life example I just tried: I wanted to create a mix based solely on the Beatles' "Maxwell Silver Hammer" which resulted in the following songs:

The Who - Pinball Wizard
CCR - Fortunate Sun
Monkees - I'm A Believer
Squeeze - Tempted
Beach Boys - Sloop John B

There's also an OK Go and Tenacious D song thrown in there, maybe to modern it up a little bit, but you get the idea.

Likewise, here are the first 5 songs on a mix based on the song "Prison Bound" by Social Distortion:

Rancid - Olympia, WA
NOFX - Bob
AFI - Totalimmortal
Clash - Death or Flory
Clash - Career Opportunities

As a fan of making my own mixes, I was skeptical at first, but Genius Mixes are usually so spot on in playing what I want to hear based on my mood that I've yet to need my own mixes since iTunes 9.0 landed.