Apple has once again dropped its estimated shipping wait time for new orders of the third-generation iPad. According to a brief check of Apple’s online store, the estimated wait for all models—including both black and white variants of either Wi-Fi or Wi-Fi + 4G models, across all capacities—is just 3-5 days, down from 5-7 business days. As has been the case in the past, the changes appear to apply only to the US and Canadian stores,…