I think this is primarily because the touch has a more extensive software installed on it, more features like youtube, safari, calendar, itunes store... whatever. and it uses up more space on the 8 gig ipod, so the actual available storage space for songs is less than on the ipod nano.
Between the MagSafe adapter issue that I read over at the Yahoo Tech pages, the iMac problems, and the iPhone suits/hacking business, you'd think Apple has quite a bunch on their plates. Well, I was browsing the net looking again for a suitable case for my iPod Touch with no avail, but I found this:
http://www.apple.com/ipodtouch/
Still says Pre-Order, even though it's out already. Probably a typo or hasn't been updated in the past few days. The Specs list up to 1750 songs on the 8Gb version but the 8GB Nano can have 2000. ... Apple needs to re-estimate their stuff it looks like. Now unless the iPod pages on the Apple site are just a mess, maybe the rumors I've seen all over the web that suggest new upgrades for the Touch, iPhone, and other products by the holidays and early Spring are somewhat true. Wouldn't be the first time.
But, this is just my crazy speculation. I'm probably wrong in this case. Site just needs an update I suppose.

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