2.8 Million

According to Asia Pulse Businesswire Nintendo shipped a total of 2.8 million DS's worldwide by the end of the year. This is far greater than the initial expectation than 2 million.

Almost all of them had been sold through retailers up by the time the New Year's holidays ended, according to the company.
Asia Pulse Businesswire

Source: Nintendojo

-Ultimate Zelda Guru