Ooble

OK, to replace iTunes, you need to:

1. make it easy to use. iTunes is in serious need of functionality, but the tiny amount of features it does have are very easy to get your head around and use.
   
2. make it cross-platform. iTunes is available on the two biggest OSes around... if you can get Linux in there as well, you're onto a winner. The problem with audio players is that firstly, none of the good ones are cross-platform so I can use the same one on all my systems, and secondly, there are no good Mac players. It used to be difficult to make things cross-platform, but there are several libraries you can use to make your life easier. And no, this does not include Java.
   
3. Add functionality wherever you can. If a feature might be useful, add it. There is such a thing as feature bloat, but avoid stuff just for the sake of eye candy (like visualisations... who seriously wants to watch their music?) and concentrate on delivering the features in an easy-to-use manner (see a) and you'll get no complaints.
   
4. Make it pretty. Duh.
   
5. Release an MP3 player that will beat the iPod, and make it only compatible with your software. And while you're at it, make your own Mac OS-beater and make the software the default audio player.
   
   Obviously, this, you can't do, which is why you'll have a hard time overtaking iTunes. It isn't, however, a reason not to bother trying.

Good luck. Let me know if you need a beta-tester.

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