Depends on how you use it. I want video, so I got the touch. It's amazing. But, I still have an 8gb nano that I would use for music probably. (applications would include at the gym, walking/running, on a plane) These applications is where the nano shines. I can put it in my front pocket and change volume by feel.
The touch cannot do this. I'm lucky enough to have both. While I do have some music loaded up on my touch, it's got mostly videos for when I'm on teh plane.