As has become customary with Apple product launches, you can expect long lines at Best Buy and Apple retail stores when the new iPad goes on sale this Friday. The only way to avoid those lines is to submit a preorder on Apple's website (or buy an Android device instead, as it were), but for those planning to do that, the wait is now 2-3 weeks, where as prior to this weekend Apple was still promising day-of-release delivery.
The shipping delay was hinted last Thursday when 16GB and 64GB AT&T Wi-Fi + 4G models starting showing a March 19 (Monday) delivery date instead of March 16. By Saturday, all new iPad models were pushed back to a Monday delivery, and now just a few days later, they're all completely sold out online, just as we predicted would happen (not that we went out on a limb or anything).
In case you fell into a coma last week and missed Apple's much hyped iPad announcement, the new device sports a Retina Display, 5MP camera with improved optics and 1080p video recording, A5X processor with quad-core graphics, and 1GB of RAM.