LTE is considered unproven technology. Apple would rather have the tech proven 99% of the time before releasing it. HSPA+ isn't 4G(AT&T and T-Mobile are marketing it as 4th generation). LTE with firmware updates can hit the 4G mark while HSPA+ can't hit the 4G mark. AT&T has started to roll out their LTE to compete.
More than likely next year Apple may roll out their iPhones with LTE when there is more areas that has LTE. You need to talk to Apple about it more than Verizon.
Since I still have a year left on my current agreement, I wasn't planning on upgrading until then, anyway. I guess I'll just wait it out until Apple deigns it good-to-go. I love my MACBook PRO and my new iPad Touch. I'm just trying to move everything to one technology. I was a PC ever since there were PCs. I even hold many Microsoft certifications. I switched to the MAC 4 years ago and will never go back.