when you have more iPods then you use..... and you still think you need a new one
I just acquired a new shuffle (still unused)... my wife just bought a nano... I still have my mini....
I still use both my video and mini. I use the mini on trips sometimes because I'm less worried about it getting stolen, and it also took me a long time to realise that a video will charge through a FireWire charger. I really want the 6th gen when it comes out, though.