"Nintendo released a cheap, profitable product (Wii remote) that was 'good enough' for low end users (casuals). Now, they plan to move up-market with sustaining innovations (motion plus) in order to reach higher tier customers (core/hardcore who want 1:1)."
That's the exact business model provided in The Innovator's Dilemma using Nintendo products to fill in the blanks. Using that book as a predictor of Nintendo's future actions (and it's been spot-on so far), Nintendo will NOT package this in with Wii Sports 2 (there will be no such game) as low end users don't give a *CEN-2.0-SORD* about more accurate controls. Nintendo is using this accessory to target the hardcore, and will most likely package this in with a core-focused product. Probably Zelda.