This is becoming very hard to predict the mindset of the customers these days. In spite of the fact that iPhone 4S looking much similar to their predecessor, iPhone 4, and a much delayed launch of the product than assured, the sales seems to be going at a very good pace, that the stores will be soon out of supply for demand. Already, as per the observation of Robert W. Baird & Co. analyst William Power many of the Best Buy retail stores around the country are out of iPhone 4S handsets, which they believe to be an indicator of the sales pace of iPhone 4S in the US market.

So what Best Buy’s up to is that they have started taking down reservation orders for as they await their next shipment. A similar report was also generated by BGR, which only reaffirms the sales pace of iPhone 4S to be doing well, better than what was being expected.

Besides, for those who missed out on the first shipment, will have to wait until the next shipment takes place, for this is sure to take time to build these devices and Apple is not sure of when they will be able to replenish the Best Buy inventory. Meanwhile, some of the other store locations have their orders coming by the end of this week.

So how the sales pace is for direct purchase with the carriers? Sprint confirmed that they are enjoying the success of “best ever day of sales”, while AT & T activated more than 1 million handsets within one week of launch.

What Apple has got to say will be the final sum up. Apple says they have sold more than 4 million handsets across the seven launch markets within the first weekend of the launch of their product.