Keep in mind, week one for Japan was two days, because it released on a Saturday. It sold almost all of its 400K shipment in that time. 3DS releases in NA on a Sunday, so it should have a full week to sell that first shipment before we get weekly numbers. (I don't think Sunday is counted in the previous week for these reportings)
Old news says big N is planning to ship 2.5 million 3DS units outside Japan by the 31st, which is still launch week for NA and EMEAA, so possibly they could all be sold in week one.
My prediction range is about (1,050,000 NA and 700,000 EMEAA) to (1,250,000 NA and 850,000 EMEAA)