I was thinking..
I ordered my rMBP on 06/18 and Apple says it'll take 3-4 weeks, but also says the delivery date will be between 07/17 and 07/23...
That's more like 5 to 6 weeks...
:Edit, oh wait... they say it'll be ready to ship in 3-4 weeks.. so shipping takes 2 weeks??!
Count business days. In addition, I believe the 3-4 weeks is until it ships and the date range is the arrival times.