Just like the iPod will never have video....
It may not be this year (i really, really want it to be), but I bet it would be the following year. Given that Tom Tom, Garmin, and a few other providers are available in the app store I cant see why they wouldnt offer the iPod touch with a GPS chip this year. Not to mention the geo-tagging for the camera like others have pointed out. Why not utilize iPhoto's location tagging across all Apple products that have a camera built in?