If you're really interested in picking up an iPhone on the 29th, be prepared for long waits and possible disappointment. The iPhone won't go on sale until 6 p.m. local time, and lines will likely start forming early (like, Oh-Dark-Thirty early). Not only that, but a supply chain expert expects shortages to leave some empty-handed for up to eight weeks.I'll cut right to the chase. In an - sent from Simon Croom, Ph.D., executive director of the Supply Chain Management Institute at the University of San Diego, to a ZDNet.com editor, he explains his thoughts on the iPhone launch and its probable supply chain issues.

"Launching any product, especially one so hyped, means that the main task is ensuring sufficient supplies are available across the US market on launch. Undoubtedly there will be shortages, service issues and challenges for call centers set upto support users. Depending on reliability of the product, there may also be a rapid ramp up in returns and warranty claims. Using a global supply chain will likely cause more of a problem 4 - 8 weeks into the 'first season' of the launch."

Ouch. Eight weeks? Croom's comments contradict earlier analyst statements that there will be as many as 3 million iPhones on hand for launch day. When asked about potential supply issues, Steve Jobs himself mentioned that more than a million people registered on Apple's site for the device, and he hoped to be able to meet at least that number come the 29th.

Given the hype and continual in-your-face-ness of the iPhone, I'd say it's a fair guess that a lot of people will be lining up on the 29th, even if it is just to look at the darned thing. Supply chains are sometimes tricky beasts to tame. Coordinating everything so that the iPhone suddenly shows up at all the Apple stores and thousands of AT&T outlets at the same moment, and in quantity, is no easy feat.

So, if we don't hear from Over The Air blogger Stephen Wellman after June 29, we'll know that he's still standing in line over at an AT&T or Apple store somewhere.