I'm not at all convinced that that it true. Maybe they'll eventually sell them when supplies are less constrained, but I'm inclined to doubt they'll have them at the outset. We'll know pretty soon, though.
I have a pretty credible source telling me that AT&T will not be carrying them. First, they are not cell phones, secondly, there are no contracts, third (and last) the 3G service is ordered right on the iPad.
These will not be in AT&T stores. They want to focus more on the cell phone plans than an iPad plan.
Additionally, iPad will not be sold through the business channels nor will the iPad data plans we eligible for corporate discount plans.
Granted, things may change in the future, but as of now, this will be the policy.