Joystiq has some face time with Nintendo’s Wii Fit Plus at E3 and the initial prognoses is: it’ll keep you fit. Again.
An interesting snippet:
The next game we tried was the “platformer” level described at the keynote. Basically a series of gauntlets involving swinging wrecking balls, sliding platforms, and jumps, it reminded us less of Super Mario Bros. and more of the diabolical Sasuke/Ninja Warrior show — not at all a bad thing. In this game, players run in place on the Balance Board, straightening your legs to jump like in the first game’s ski jump event. After each successful run, you’re put into a harder level.
Full thing plus screenshots, through the link.