I expect iphone /ipod touch to easily surpass DS sales because they are more mainstream devices.
EVERYBODY has a cell phone, pretty much EVERYBODY has some form of music player. So out of all those units sold, how many were sold to play games? 0. how many DS were sold to play games? 132 million. 1.5 billion downloads also includes everything free. When you start to factor in how much of that software is music, videos, gimmicky apps, free games, or $! games, you realize that there isn't much money to be had for a serious game developer. I wouldn't be surprised if Nintendogs alone has made more revune than the entire app store.
There is more money to be had on a dedicated gaming device.







