At the time the did optomize the system for the time they released it. Nintendo has always released a new version of their current Handheld system...the only expection being the GB Color.

GB -> GB pocket
GBA -> SP -> Micro
DS -> DSLite

I might even argue that the GBColor was just another enhanced version of the Gameboy. This is far from new on the handheld market.

Wii means nintendo made another retarded marketing move.