Woohoo! Thanks to various regulatory rules, the iPhone 5 on Verizon is GSM unlocked.
I can confirm that the Verizon iPhone 5 is indeed GSM unlocked. Even though I bought an iPhone 5 from Verizon under contract, I was able to cut down my AT&T Micro SIM, and use it in my Verizon iPhone 5 to pick up an AT&T signal. By doing so, I was able to hop onto AT&T’s HPSA+ network, or “4G” as they so ridiculously name it.
Cut your SIM card down at your own risk!