My guess is Nintendo has a 2nd factory online now and is capable of up to 2 million a month. They are probably planning or already setting units back for the big three releases and the holidays.
Looks like July to pass 360 WW is becoming more of a reality.
You mean another subcontractor building units. Nintendo uses Asian manufacturers like Foxconn and Asus just as Sony and MS do to build their consoles. Of course that's oversimplifying the case, because you also have to coordinate with the parts manufacturers to deliver enough components for the increased manufacturing capacity.