There has been speculation forever about a wireless iPod and who knows if it will happen, but Portalplayer is partnering to offer it

http://portalplayer.com/news-and-events/CSR_PPI.htm

and considering that 95% of Portalplayer's revenue is coming from Apple, it surely seems to imply that they believe that Apple at least *might* have some interest.

This has been discussed (and speculated) on the maillist before, but I do believe that if Apple includes bluetooth or WiFi on their player, not having it will be like having USB 1.1 on your player.