When it comes to the supply channel, I’ve noticed that Apple usually tries to err on the side of caution: better to have too little in the channel than too many. Shortages are better than unsold stock piling up in warehouses. (Remember the sudden drop-off in flat-panel iMac demand, for example.) But the iPod mini, on the other hand, is in short supply because there just aren’t enough of those little four-gigabyte hard drives available; as a result, the international release has been pushed back from April to July.

So, another parts shortage. So what does it mean? It’s at least in part due to demand forecasts that turned out to be too conservative; they would have ramped things up differently — tried to order more hard drives from Hitachi, delayed release, or delayed international release. But then if they weren’t expecting limited supply and strong demand, they wouldn’t have opted for a two-tier rollout. In any event, it’s quite different from the conventional wisdom, which was that it was going to bomb.