My with PC loving friend:

Him: Hey I downloaded Apple's MP3 player you said was good.

Me: oh yeah, you like?

Him: Doesn't play WMA - or am I doing something wrong? None of my music works.

Me: No doesn't support WMA - but it does MP3, AIF and WAV. Even better, it supports AAC which is much better than WMA.

Him: Oh yeah, but I have ripper all my CD's in WMA.

Me: Well - it will save you space if you re-rip them using iTunes and they will sound better.

Him: Meh, I've got too many CD's, WMP9 works well for me. iTunes would be good if it did WMA.