There are now 184 million domain name registered ,according to the he second quarter 2009 Domain Name Industry Brief published by VeriSign.
The most popular is still .com .followed by .cn (China) , .de (Germany) and .net .
Strange as it may be, .ar (Argentina) had the fastest growth with an eight percent quarter over quarter.
"The overall base of .com and .net domain names grew to 93.5 million domain names during the second quarter of 2009. This represents a one percent increase over the first quarter of 2009, a seven percent increase over the same quarter of the previous year, and a 28 percent increase over the second quarter of 2007. "
For more details check out : www.verisign.com