Google Inc co-founder Sergey Brin said on Thursday advertising on social networking sites such as Facebook and MySpace was getting better, but was still not perfect.
"In general, it's been improving but we still have a long way to go," Brin told reporters on the sidelines of a conference in Jerusalem to mark Israel's 60th anniversary.
Google Chief Executive Eric Schmidt said that in January the company was having trouble making inroads selling advertising into what is now the hottest market on the Internet.
Brin said it would take time to find the best formula to develop the social networking advertising business, to develop the right technology and to educate advertisers and users.