Pop goes first, then AS Movies. I would think from reading the boards that Music is slightly preferred over Sports, but those two are kind of interchangeable most of the time.
When I called on Thursday, I had my alternate choices written down -ASMu, ASSp, POP and last would have been ASMo. Luckily, my first choice was available.
I don't think that anyone will have a problem getting their first choice this early.