it's still the best selling console with female games like that just dance or whatever really catching - and anyone underestimating that market wants to look at some of the Imagine DS games and how they sold.
On top of that we Have Zelda, SMG2, Metroid other M, Pikmin 3 (hopefully), Red Steel 2, Silent Hill (i'm in uk - haven't had it yet) and a spew of Wii Ware titles like Super Meat boy and that game with the shadows.
It's a long way off dead yet - it'll last longer than the average 5 year figure that gets thrown around for a consoles life cycle.