Handheld market this year for the month compared to where it was a few years ago ...
March 2013 -
3DS - 230k-ish
Vita - 33k-ish
March 2007 -
DS - 500k
PSP - 180k
March 2008 -
DS - 690k (wowza)
PSP - 297k
March 2009 -
DS - 563k
PSP - 168k
March 2010 -
DS - 700k
PSP - 119k
The handheld market has never been the same since the launch of the iPad in spring 2010 and the rise of the iOS marketplace. Things like Angry Birds, Cut the Rope, Fruit Ninja, etc. all become the first real iOS "blockbuster" hits in 2010. Not a coincidence IMO.