http://www.4colorrebellion.com/archives/2007/12/12/one-ds-sold-every-five-seconds-in-2007/
I guess it really DOES print money 
If I remember correctly, the DS is at 20 million in Japan.
Being an awesome system also helps.
Having a shitload of good games helps too.
Especially if 90 percent of the games aren’t shoddy remakes of other games.
Not quite 4 years yet. It came out in late '04 afterall. But yes, it does help to have a great library of games instead of a proprietery video format nobody uses…
I haven’t bought a DSlite. Haven’t felt the need =)
God I love Nintendo.
So…Nintendo still king of Handhelds…nice.