iPad 2 sales began at 1am Pacific earlier today and Apple has already extended shipping times for new orders from the intially-listed 3-5 day to 2-3 weeks.
Only the 16GB Verizon iPad 2 WiFi+3G model currently retains the 3-5 day shipping designation.
The original iPad sold 300,000 units the first day, 500,000 the first week, and 1,000,000 in the first 28 days.
See the current iPad 2 models and shipping times via Apple Store Online here.
MacDailyNews Take: If you want an iPad 2 on Day One, quick, get in line!