Too soon. DS didn't go crazy till the Lite hit. But... there's every chance 3DS sales will balloon down the line like the DS did - 2D Mario, Pokemon, Smash Bros., hardware revisions are all still to come, as well as plenty other titles likely to sell well.
If the Vita fails to recover properly in Japan, that should be to the 3DS' benefit too.
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We are living our lives
Abound with so much information