iPad is the fastest selling product from Apple all time! 
35.1 million iPads sold during 1st quarter - March 2011
15.43 million iPads sold during 4th quarter - December 2011

11.12 million iPads during the 3rd quarter – September 2011
9.25 million iPads sold during the 2nd quarter 2011 – June 2011
4.69 million iPads during the 1st quarter 2011 – March 2011

iPad 2 is just now launching in China this quarter.