Yeah, I read that entire thread and honestly, I still stand by what TooDark said. I think the VZW model is meant to only be used by int'l GSM carriers. What people do with the device after going to a sketchy website and unlocking AT&T SIM cards is up to them. I'll keep an eye on MacRumors, however, to see if anyone posts any long-term results of doing this. It won't take AT&T long to figure out what's going on (not sure if they'll care). It should be noted that this was done with an AT&T iPad 2 SIM, so if you try to get away with just popping your iPhone micro-SIM into an iPad get ready to get some nastiness from Big Blue.
After reading that thread, I'm now just going to stick with the AT&T model. If I have to go rigging SIMs and messing with APN settings in order to get the VZW model to work on AT&T's 3G network, thanks but no thanks. I'd rather just stick with the (less congested and faster) AT&T LTE network. All of my regular traveling destinations are covered so the smaller LTE footprint turns out to be a non-issue; besides which, from what I understand AT&T's HSPA+ is still faster than VZW's 3G so when/if I'm out of LTE range, I'm still trucking along quite fine. (Still waiting on that tethering option, thought, AT&T!)
Thanks for the info, anthrovisual!