I just browsed my artist list and selected White Stripes -> White Blood Cells. Half way through playing the album I noticed that one track played in the wrong order.

The reason was that a different genre tag had been set for a song. It appears that "Sort by song information" looks at genre before track number.

This seems like a bug to me, especially when selecting an album. Surely the sort order should be Artist, Album, Track number.

Bug 99 (feature request) looks related to this.