I am just short of 6000 songs and I had three NIN tracks come up in a row yesterday afternoon. And within 10 tracks in either direction, 2 more NIN tracks.
The odds would be astronomical, if they empeg's shuffle wasn't somehow buggered and responsible for this.
And if you want to figure out odds, you should look at the odds for 3 songs by any given artist, not for three specific tracks (because those odds are the same for any other 3 specific tracks). I have a few NIN albums which contain about 78 songs and then some others from compilation discs (let's say 85 total to be very safe).
Bruno