Examiner

505 Games and Majesco Entertainment announced today that their hit dance/exercise game franchise, Zumba Fitness, has sold over six million copies worldwide in less than fifteen months. These numbers include sales from Zumba Fitness on Kinect for Xbox 360, Wii, and PlayStation Move as well as Zumba Fitness 2 for Wii.

Sales are sure to go up after the release of Zumba Fitness Rush for Xbox 360 last week (you can currently get $10 in Amazon credit when you purchase Zumba Fitness Rush). The sequel features 42 new songs and routines (ten of which are exclusive to Kinect), 24 international dance styles, and six celebrity Zumba instructors. The game will also be available in Europe starting tomorrow.

505 and Majesco also took the opportunity to announce some details for two upcoming downloadable dance style packs for Zumba Fitness Rush scheduled to be released later this year. The first is a Bollywood style pack set for release in May and the second a Hip-Hop style pack coming out in September. Both will include three brand new songs and be priced at 400 Microsoft Points each.

http://www.examiner.com/xbox-360-in-national/zumba-fitness-franchise-surpasses-6-million-sold

For a comparison, VGChartz has the total sales of the franchise at 7.31 million as far as I can tell.

Most of those sales come from the original on Wii, which this site has at 4.77 million.

My girlfriend who is a huge Zumba fan tried Zumba Fitness Rush (basically Zumba Fitness 2) on my 360 and immediately said that Dance Central 2 was miles better and more fun.
That was a moment where I was actually proud of her :D

Majesco has managed to do pretty well for themselves since they turned to doing casual titles. I'm always surprised by Zumba sales in Europe.