It could be argued that Etrex series isn't really 'missing' anything by NOT having a touch screen. I don't have any experience with the Garmin touch's or know how they are built, but I've had a few problems with my Trimble data collector touch screens at work. From what I've been told by the tech's when I have to send the units back for service, the screens have a contact area around the screen perimeter, under the exterior casing, that has trouble when dirt or grit works its way into the unit. In most of my cases, things were fine until I used the unit in the rain, which washed the grit into the contact area and 'shorted out' the touch screen. Basically the touch feature of the touch screen stops working.
Like I said, I dont have any experience with the Garmin touches, but I'm leary of them based on my experience so far. Hopefully Garmin has a better system and they do not have the same problems as I've encountered with similar equipment. It would be nice if they perfect things as I'm a big fan of that type of interface.