A note on Apple’s retail page states that Apple Stores will now open at 8am every day except Sunday to help cope with the demand for the iPhone 3G.

Your favorite Apple Retail Store is making it easier and more convenient to purchase an iPhone 3G. All stores will now open at 8:00 a.m. every day but Sunday and, to accommodate demand, we’re adding staff to help you get up and running as quickly as possible.

While standing in line for the iPhone 3G store staff will “prequalify” you which will involve things like administrative paperwork and credit checks. If you pass “prequalification” then you will receive a ticket for an iPhone 3G which can either be redeemed on the spot or before 6pm that day (4pm Sunday)

Apple also recommends checking iPhone availability using the iPhone Availability checker which updates every evening after 9pm.