Hmm, well, I now see
/bin/kobo_config.sh in both the Glo and Touch v2.1.5 firmware releases, which returns the product name of the device (mentioned
here).
I'm hoping that means for future release, a file will be added (say, required_product), that lists the product it works for... With those two things, it shouldn't take more a few additional lines of bash code in /etc/init.d/upgrade-wifi.sh to prevent the firmware from being applied to the wrong device...
I did see that the kobo_config.sh script
was not in 2.0.0.c, so checking may not have been possible with the factory Glo - but hopefully from now on out?