It's only because AT&T finally got some of their crap together and resolved a lot of the issues users have been complaining about for years (even before the launch of the iPhone.)
There will always be areas where AT&T has bad coverage (and same with Verizon) but the issues with bad voice quality, bad WCDMA migration, crappy backhauls, and some bad iPhone configs from Apple have mostly been addressed at this point.
Due to this, I most likely won't be waiting in line for a Verizon iPhone on launch day...but still may get jump at one point. For me it will depend on the LTE rollout and data pricing
There will always be areas where AT&T has bad coverage (and same with Verizon) but the issues with bad voice quality, bad WCDMA migration, crappy backhauls, and some bad iPhone configs from Apple have mostly been addressed at this point.
Due to this, I most likely won't be waiting in line for a Verizon iPhone on launch day...but still may get jump at one point. For me it will depend on the LTE rollout and data pricing