The 3DS is out now so the lifespan of the DS is gonna be end, but I hope it won't be soon. I remember the GBA still had new games until 2008, 4 years after the DS, such as TMNT in 2007, which is a quite good beat em up game. Rhythm Tengoku, my favorite, released only in Japan in 2006. Final Fantasy Advance was released in 2006 too. The last game released in US was Samurai Deeper Kyo in February 2008. I hope we will have new DS games until 2013 or 2014.