Does anyone know why my iTunes is playing songs in reverse order?
I am running Mac OS X 10.6.8 with iTunes 10.3.1
I had a similar problem a while back.
For some reason, it seems to happen whenever you sort albums in descending order.
What fixed it for me was going to the album overview (the grid with all the covers), then selecting
View -> Sort Albums -> Ascending.
After that, the playback order within the individual albums went back to normal.
Hope this works for you as well.