Check it out:
http://winnetmag.com/Article/ArticleID/41423/41423.html
"Exclusive: HP Working to Get WMA on iPod
HP's blockbuster deal with Apple will have one exciting side effect, I discovered today. The company will be working with Apple to add support for Microsoft's superior Windows Media Audio (WMA) format to the iPod by mid-year. You heard it here first."
Thurrott's site is the closest thing (that I know of) that the Windows world has to a Mac style "rumor site", but he's been around a long time and is pretty respectable. Although I prefer AAC to WMA, you have to admit the WMA support on the iPod would open up a LOT of options for iPod owners to purchase music.