iTunes shuffle

So I use iTunes for all my music, which means I basically live with iTunes as my soundtrack. Plays at work, when I sleep, all the time really.

I haven't listened to a lot of industrial stuff in years, cause of the whole techno thing, but I was feeling it today and got some Thrill Kill Kult and Skinny Puppy. Played a couple songs. Got back to work, with iTunes on shuffle, and what comes up next, randomly? KMDFM. Then a Lords of Acid remix, the only one out of hundreds of tracks. How the fuck did iTunes randomly select two more industrial tracks? Blows my mind.

There's nothing in the 'Genre' field either, so it can't just be that simple. Anyone heard anything about the randomizer algorithm? I can't believe it's FFTing my music and finding other songs with similar frequency profiles or some such, but if it is, that's awesome.