The biggest difference between the two devices is simply in the application of user experience. With the iPod Touch, the UX is created for you. You don't have to think about it as Apple has determined that. For many users, this works. The IT on the other hand has a more user defined UX model. This too works for many users. However, there are downsides to both, as have been noted here and on various other forums.

My most common assessment in this compairson has been that Nokia is closer towards making a device that will blend into one's expectations better than Apple. This is not to say that Apple missed the boat; they didn't. But they did show that with the IT that Nokia should do more steering of the global UX impact of this type of computing, and then give room for the IT community (developers and users) to play within this soapbox. Doing so will make the IT a clearer compairson to the Touch, and probably to the idea of tablet computing as lots of companies have been trying to do since the Newton/Palm Pilot.