I'm not a huge DDR fan but once being a supervisor at Playdium, I know several people that are.
Adding controller motions sounds too complex for me personally, but I'm guessing there are many DDR pros that might like the extra challenge.
And the actions you can perform with the Wii Remote and/or Nunchuk could be more exciting than a similar game on a competing console with inferior motion controls *coughSixaxiscough*.
This could be the hottest party (at least, involving dance pads and clothes), indeed.