DKII on 15 June 2009
Its install base is too low. The Balance Board has a huge install base and even that is only lightly supported.
Also I've heard officially that a third-party Wii headset would easily be possible but it's not financially viable given the current marketplace (no one using Wii Speak, no games supporting it, etc.)
I think Nintendo would need to push it more themselves; I think they expected it and Animal Crossing Wii to do better than they have; maybe they decided against pushing it too much and that's why it wasn't a mandatory bundle with AC Wii + Wii Speak last year. Dunno.
