by , 11:50 AM EDT, June 25th, 2007

June 29 - the day Apple releases the iPhone - has been dubbed "iDay," although for Apple it might as well be called "ka-ching day." Based on some estimates, the iPhone could bring in over US$200 Million in revenue the first day it is available, according to TheStreet.com.

TheStreet.com's Scott Moritz figures there are 162 Apple Stores and 1,800 AT&T stores in the United States. That makes for 1,962 retail outlets where consumers can go to purchase an iPhone.

"So with 1,962 stores and let's say 200 phones per store, Apple stands to sell some 392,000 iPhones," he said. "With each phone selling for an average price of $550, Apple stands to take in $216 million in revenue on the evening of June 29. And that's not including online sales."

Selling 392,000 iPhones on the first day would be an amazing feat for Apple and AT&T since the combination iPod and smartphone won't go on sale until 6 p.m. local time, leaving only a few hours for sales in each time zone. So far, the most optimistic sales figures have come from the likes of Piper Jaffray's Gene Munster, and he is estimating that 200,000 units will sell in the first two days.

Should Apple hit Mr. Moritz's estimates, however, that could translate into an extra $0.02 per share, or an additional $2 million in profit, assuming that every 1 million iPhones sold adds $0.06 per share bottom-line profit. The numbers also mean that Apple would be looking at about triple the revenue it brings in on a typical day.

Despite Mr. Moritz's optimistic predictions, Apple and AT&T may not be able to process transactions fast enough to hit his numbers. Apple also will need to have enough product on hand at retail stores, and for now no one from Apple or AT&T is saying exactly how many units each store will have on hand.

Apple is currently trading at $124.8292, up 1.8295 (1.49%).