But don't those devices have maps on the device itself? Or are they merely coordinate loggers? If the touch is not used for that, I can't see much benefit for touch owners knowing that they are are 12.3456 by 323.7395. The maps are greatly needed.
Yes and yes. The eTrek does include maps (and it has a small amount of flash memory for that purpose ... 64 MB or somesuch ... this is large enough to hold 100k maps for all of CA and 24k maps for most of the places I hike without too much reshuffling) and plots your position on the on-screen map. This is great.
On the other hand, there are also highly useful coordinate loggers, which typically have no display whatsoever and/or which display nothing more than current position and statistics on the tripe (how long, how fast, average speed, current speed, etc). These are great for fitness (a HUGE step up from the likes of the Nike+ idea), as well as for outdoor photography (the track logs can be automagically matched up to all the photos you took in Yosemite, so you can see where you were standing in the park when you took each picture ... granted, this still doesn't tell you which direction you were looking, but it's better than relying on "Yosemite" being put into the photo comments tag).
IMHO, Apple (or a third-party dev) could easily create a Garmin ForeRunner killer app (no turn-by-turn directions, just log the route, show stats on speed/distance throughout, and sync the track log to the computer when you get back home). It would take a little more effort (primarily because the map files are all proprietary right now, but a partnership with Topo or the like would brush that issue aside) to get a really nice eTrek killer app.
IMHO, Garmin is a really fat cat company sitting on top of their handheld devices. The devices are rather well designed, which is why Garmin does such a great job. On the other hand, the software kinda really stinks (especially for the Mac, but the byzantine Windows apps I need to use to change maps on my eTrek are just plain painful to use as well), the devices are way too expensive, and map updates are their "blades" (if there are two similar models, razors and blade where the razors are cheap but the blades are expensive, and iPod and songs where the iPod is the profit center and the songs are dirt cheap, Garmin is running the iPod and blades model ...)