They just follow the usual Nintendo handheld tradition, the main model, a cheaper smaller version, a model with new features, etc, so it is the usual Nintendo way of giving a bit more of life to a handheld and see if there are double or triple dippers.
And counting the 2DS out already? Sure, it has done badly in the West, though it still has Japan to go, and who knows how it will fare there, its cheap price can actually be factor in Japan, the country is not in a good economical situation, so this cheap option may fare well, though on the other side, the size of it may hinder it.
COMG guide to points: 1 point = Raging. 2 points = Beasting. 3 points = Tearing it up. 4 points = Berzerk. 7 points = Rampage. 12 points = Burst. 15 points = god mode. 20+ points = DIVIDING BY ZERO!!! 40+ points = Youkai (originally Pokemon).
-1 = Negabeasting. -5= NegaRampage. -10 = NegaBurst
