Japanese software sales so far (Famitsu)

– Blue Dragon Plus (NDS, Mistwalker): 39,401 units sold
Release: 09/04/08

– New Super Mario Bros. (NDS, Nintendo): 5,281,886 units sold
Release: 05/25/06

– Hajimete no Wii (Wii Play) (Wii, Nintendo): 2,478,465 units sold
Release: 12/02/06

Source