Go to the expense? The PSP is on its arse and Sony are in desperate need to extend its life.
The Go is just a way of building up their back catalogue of PSP1 titles on the store and getting people ready for the next generation to start. If they're lucky its sells well but highly doubt it. At least it keeps the brand fresh and from people forgetting all about it.
Microsoft are rumoured to get into the handheld market. Do you think they'll not go to town on it? Two analogue sticks, touch controls, BIGGER screen.
Three years? No way man. We want a new device with more power soon.
Gameboy Advance, June 2001
Game Boy Advance SP, March 2003
DS Phat, December 2004
Game Boy (Advance) Micro, September 2005
DS Lite, June 2006
DSi, April 2009
PSP Phat, March 2005
PSP Slim & Lite, September 2007
PSP 3000, Octobmer 2008
PSPGo, September 2009
PSP2, December 2010-March 2011