Why is the iPod so successful?

Here are some thoughts I had why the iPod is so successful

• Beautiful simplistic design
• Kick-ass simple and good user interface
  
• Appeals to men and women (Not a boys gadget, not a girls accessory)
• Integrates with iTunes and the iTunes Music Store (which are kick-ass simple and good on their own)
• Not feature bloated, only the features that people need, and the included features are kick-ass good (Want a FM tuner? Go buy one on the iPod after-market)

With this this in mind, we can look at the shortcomings of the iPod (which real don't matter that much)

• Battery life could be better (its enough to hear music a whole day through)
  
• No replaceable battery (which only would make sense, if you had a standard battery; Besides, a replaceable battery would make the iPod only heavier and bigger, if it should offer the same battery life)
• No standard replaceable battery (but AA batteries wouldn't give the battery life you want on such a device and there is no standard LiIon battery)
• Its hard to get the music-files back from your iPod, but I guess that is not Apples fault, but the fault of the music industry (there are ways around this)
  
• iPods Fairplay doesn't play well with others (WMA and the like, but who needs them anyway)
• Some iPods had some problems with the headphone jack and noise being audible (but you should be able to get the iPod replaces by Apple; Nevertheless, Apple should get their shit together)