So, did the iPhone 3G make its July 11 Japan debut with a bang? Yes, as you've already heard if you've listened to news at all. Several SoftBank Mobile sales outlets in Tokyo each faced queues of over a thousand shoppers; the Ometasando location had 1500 in line before SoftBank capped it with a "sold out" sign, after which the line just kept going with people lining up for the chance of a phone the next day. Throughout Japan, iPhones flew out the doors fast, to the tune of 25,000 units total the first two days.

Not surprisingly, the iPhone 3G was the top-selling phone that day, according to the BCN Ranking service: the 16GB model accounted for 36.8% of all mobile phone unit sales and the 8GB model for another 8.1%, totalling 44.9% - amazing performance in a market where any two-digit percentage is a rarity. The next day, though, numbers were more restrained (as was supply): a 10.3% share for the 16GB iPhone 3G and 5.6% for Casio's water-resistant W61CA from au, with the 8GB iPhone 3G coming in third after that.

Unit sales by carrier on July 11 broke down to 51.6% for Softbank Mobile, 26.4% for DOCOMO, and 19.6% for au/KDDI. On the 12th, though, SoftBank racked up only 27.7% of sales – again, says BCN, partly due to simply not having enough iPhones on hand to sustain the surge. For either day, the numbers represent a big reversal of the status quo: for the month of June, for example, unit sales share by carrier were 52.5% for DOCOMO, 32.8% for au, and only 13.8% for SoftBank.

As of today, many SoftBank shops around Japan continue telling eager would-be customers that they have no iPhones and don't know when the next shipment arrives. Can SoftBank stay on top of its momentarily massive market share? That will largely depend on the iPhone supply.

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