Maybe they thought they could steal the iPod idea, just like everything else they've stolen. 
Aqua
I often see people alleging Microsoft for stealing all ideas from Apple, but I think MS guys ARE hard-working and haven't stolen anything since Windows 1.01. 
Anurag, the controversy goes back to the very earliest days...and while I am sure the MS guys today are hard working...What of it..? It doesn't mean the taint of theft should be ignored or papered over. Theft is theft.
As a matter of fact, there was a recent controversy (you might be aware of this) on this issue. The Mac fans blamed MS for "ripping off" Mac OS X to develop Vista. Now that was obviously a sense-less allegation.
I wouldn't be so sure that is a baseless accusation. Remember, Balmer has repeatedly claimed that Vista has swags of Unix code in the system and that in consequence, these bits of 'unix' are what they are using to intimidate main Linux players such as Canonical, and others.
Also, the first users to point out the remarkable similarities between Vista and OS X, were not Mac users. In fact it was the army of Vista Beta users, who made the comparison. Afterall, they were the ones using X86 chips while Apple was still using PPC chips.
At least that is how I read it..
Cheers
Aquafire