This issue must, must be incorporated into an appraisal. That said, Apple hasn't been to harsh in going after domains that promote its products. I think you're probably looking at low/mid xx on ipodphones, with a lot more to the right buyer.
Motorola are launching the iTune mobile in the US now, so excelent timing!
I have aquired some domains for the same reason:
mobitunes.us
mobileitunes.us
musicnano.com (for the new iPod "nano").
ipodmoto.com